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MAGNETS Lesson 1 Group Grade(s) 4&5 Week Day Materials/Equipment: Pre-Assessment Survey for each student Small baggie of objects (1 baggie for each group of 4). Each bag should have one of each: paper clip, nickel, quarter, standard house key, 1”x1” square of aluminum foil, binder clip, a piece of scrap paper, 2-inch length of pipe cleaner, a ½ inch chunk of staples, a crayon, a popsicle stick or toothpick, a plastic bottle cap. See tips section for info on substitutions. 2 magnets for each group of 4, either shape is fine Pencils Magnets Testing Handout (1 for each group of 4) Activity Name: Magnet Testing Rotation or Session # 1 of 8 Goal/Objective of Activity: Goal: Get a baseline assessment of the students’ knowledge about magnets. Objective: Students will be able to define the word “attract” and give two examples of items attracted to magnets and the reasoning for the attraction. Students will be able to give a basic definition of a magnet. Students will be able to name at least one of the specific metals that are attracted to magnets. Background Information for the Teacher: Magnets are useful things that we don’t think about all too often. We use them on latches on doors and cupboards, to hold up refrigerators arts, and they are an essential part of electric motors. There is an invisible magnetic field around each magnet; it is either pulling (attracting) or repelling (pushing away) the things around them. In this unit we would like for youth to learn these three things: 1. Magnets can attract (pull) and repel (push) items in relationship to the magnets. 2. Magnets will attract and repel other magnets because of the poles each magnet has. 3. Only certain items are attracted or repelled by magnets. Please remind students of safety rules for each lesson. For this lesson, remind students of the following: The magnets can break easily. The magnets should be kept close to the tabletop and handled carefully. The magnets are also stronger than average household magnets. Do not hold magnets up to or near one’s face. Also do not put magnets near computers or cell phones. 1 Activity Instructions: Pre-Assessment: Distribute the Magnets Pre-Assessment handout. Tell students that it is okay if they do not know an answer and that they should take an educated guess. Allow 5 minutes for the assessment. Collect for future grading and data collection. If your students have access to a computer lab, the assessment can be taken on Survey Monkey. Opening: 1. Ask students to share what they know about magnets. Possible responses: things you stick on your fridge, things that stick to metal. Validate responses. Don’t worry about giving a definition of magnets just yet. 2. Introduce the vocabulary word ATTRACT and ask them what they think it means in general. Possible responses: when you like something, when you’re drawn to something, when you want to be close to something 3. Ask students what they think the word attract means when you’re talking about magnets. Possible responses: When a magnet “likes” something, when a magnet is drawn to something, when a magnet sticks to something. 4. Explain that magnets can attract other objects, which means they can pull on the things around them. When items are attracted to a magnet, they are drawn to the magnet. 5. Explain that the question for today is: What kinds of objects are attracted to magnets? What you will do: 1. Divide the youth into groups of 4. Review safety rules. Give each group the Magnet Testing Handout and the baggie of items. Do not give them the magnets yet. 2. Have one student read the question and background information sections. Then explain that a Hypothesis or Prediction is an educated guess. Explain that each group will make its own overall prediction about what types of objects are attracted to magnets. 3. Read through the procedures section with them. Answer any clarifying questions. Point out that they will have to make a prediction for each item before they can get their magnets. 4. You do not need to model how to fill out the P, O, E chart. Point out the example that was done for them on the chart. The example on their handout looks like this: Item P (Predict) Plastic Magnet will bottle cap not attract O (Observe) Magnet did not attract E (Explain) Magnets do not attract plastic 2 5. Explain that they should now make a prediction for each item in the baggie. 6. When all of the predictions have been made, distribute the magnets to each team. 7. Each team should then try the magnet with each item and record what they observed along with a brief explanation. The observation will either confirm the prediction or not. 8. Have youth share the results of their test 9. Clean up the activity. Debrief: Ask these questions to check for understanding: 1. Can anyone explain what a magnet is? What’s it made of? (Metal, usually iron) What does it do? (attracts other objects to it, mainly metals) 2. What kinds of items does a magnet attract? We already said it, but let’s be super certain. (Metal) All metal? (No, not all.) 3. What are some of the metal items that were attracted to the magnet? (paperclip, binder clip, staples, pipe cleaner) What do all of these items have in common. (They’re metal.) Do we know what kind of metal? (No.) 4. The paperclips, binder clips, bobby pins, staples, and pipe cleaner wires are all made of steel. What can we now say about steel? (STEEL is attracted to magnets. Steel is a mixture of metals, also known as a metal alloy, but it mostly contains IRON. Iron is the most common metal attracted to magnets.) 5. Magnets attract ferromagnetic metals like iron, nickel, and cobalt. Can you think of anything made of iron, nickel, or cobalt? (Iron: cast iron skillet, nails…pure nickel and cobalt items are harder to find). 6. What are some metal or metal-like items you thought would be attracted to the magnet but were not attracted? (keys, coins, aluminum foil) Ask these questions to encourage critical thinking: 1. Why don’t you think the keys, foil, American coins and other metal-like items are not attracted to the magnets? (Maybe they’re not the right type of metal. Maybe they’re a mixture of metals that don’t quite work.) Both answers are right. Most of these items are made of brass or aluminum or metal alloys (mixtures of metals) that are not attracted to magnets. The US nickel, for example, is 75% copper and 25% nickel - not enough nickel to be attracted to a magnet. Ask these questions to encourage reflection: 1. Which things today were a confirmation of what you already knew? (Answers will vary) 2. What was surprising or caused you to tweak your thinking? (Answers will vary) Tips and Additional Resources: 1. The first activity was adapted from AAAS’s lesson plan. You can see the original lesson plan here: http://sciencenetlinks.com/lessons/magnets-1-magnetic-pick-ups/ 3 2. You can make the baggie of items work for you in terms of what you have available. If you change up the items suggested on the materials list, that’s totally fine. Just make sure you have a variety of items that fit into these categories: (1) items that are attracted to magnets, (2) items that look like they would be attracted to magnets but really aren’t, and (3) items that are clearly not attracted to magnets. Remember that the answers to the debrief questions will have to fit your new materials. Note: In a lot of magnet lesson plans online, you will see needles and nails as suggested materials. We took out needles and nails from our lesson plans for safety reasons, and we would like you to stick to this decision as you assess your materials list. 3. As the students work in groups, make sure you circulate throughout the room. Make sure that each group has an overall hypothesis/prediction before you give them their magnets. As they work through the data table, help them if they need it without overcorrecting or giving them answers. Once they get to the question section after the testing, help them understand words like “data” and “variable.” Variables are factors in the testing. For example, the size of the objects or the strength of the magnets could be variables affecting their results. 4 MAGNETS Lesson 2 Group Grade(s) 4&5 Week Day Materials/Equipment: Two ring magnets for each group of 4 (If you don’t have enough ring magnets, some groups can use two bar magnets. These groups might need more help. See the demo video for tips.) Cotton string (1 piece per group of 4; it should be about 10”-12” long) 2 small colored stickers per group of 4. Students will use these to mark the like poles. Label dots cut in half work well. One magnet that has already been labeled with north and south poles. The PL should hang onto this magnet and use it to check the students’ results. One compass per class. You can use your smartphone compass ahead of time to figure out where North and South is in relation to your classroom. The kids do not need to see the actual compass for this activity. They just need to know which way is North and which way is South. You might use painter’s tape to “draw” a large compass in the center of the classroom for the students to see. Have the 4 “rules” for magnets written on the board. Activity Name: Labeling Magnets Lab Rotation or Session # 2 of 8 Goal/Objective of Activity: Goal: The purpose of today’s lesson is to explore the poles on a magnet and the attraction of opposite poles and the repelling of like poles. Objective: Students will be able to name the two poles of a magnet. Students will be able to identify which poles attract each other and which poles repel each other. Background Information for the Teacher: A magnetic object is pulled toward the magnet by a magnetic force from a magnetic field around the magnet. The magnetic field holds the magnetic object and magnet together even when they are being pulled in opposite directions. The strength of the magnet determines how strongly they are held together. Only objects containing certain metals are attracted to magnets. They are called ferromagnetic metals. The most common ferromagnetic metal is iron. Other ferromagnetic metals include cobalt and nickel, but we see those less in our everyday lives. Magnets can also attract or repel each other. Magnets have north and south poles. Like poles repel one another and opposite poles attract one another. Be sure to discuss the vocabulary word attract (to pull ), repel (to push apart), neutral (neither attract nor repel), poles (north and south poles, opposites attract, like repel). See the diagram below. You might want to create a poster of this image for the students to see. 5 Activity Instructions: Opening: Start out by telling the students the following “rules” for magnets. 1. There are a few rules about magnets we need to learn today. Rule #1: Every magnet has a north pole and a south pole. You usually see them labeled as “N” for “north” and “S” for “south.” Even if you cut a magnet in half, both pieces will still have a north pole and south pole. 2. Rule #2: Like poles will repel each other. Repel means to push away. So, for instance, a north pole of one magnet will repel or push away the north pole of another magnet. Similarly, the south pole of one magnet will push away the south pole of another magnet. 3. Rule #3: Unlike poles will attract one another. For example, a north pole of a magnet and a south pole of another magnet will attract one another (or pull toward one another or stick together). One way to remember this is, “Opposites Attract!” 4. Rule #4: The north pole of a magnet will always be drawn to the North Pole of the earth. The south pole of a magnet will be drawn to the South Pole of the earth. This is how compasses work, which we will see in Lesson 4. 5. Today, we will be using these rules to label the north and south poles of two magnets! What you will do: 6 PART ONE 1. Divide youth into groups of 4 2. Distribute the string, two ring magnets or two bar magnets, labeling stickers, and a pen to each group. 3. Tell the students to use the first 3 “rules” of magnets to label the like sides of the magnets. 4. Explain that they should hold the magnets close together to see which sides repel and which sides attract. They should be able to determine which poles are alike and which are different. 5. At this point, stop the kids and say, “Knowing our three rules, you now have to mark which sides are like sides. Which ones would you mark with stickers? And how do you know?” At this point, they do not know if the “likes” are north or south. If they are holding two sides together and the magnets are repelling each other, then they would know that the two sides that are facing inward are like poles. Conversely, if the two sides stick to each other, they will know that these are unlike poles. That’s really confusing, we know. You need to do this yourself a few times to make it sink in OR watch the training video. The link is on THINK Train. PART TWO: 1. Tell the students they now need to find out which side is north and which is south. Stick the two magnets together. Tie them together on ONE string. Hold that string up and let the magnet sandwich dangle. The north pole of the magnet will align itself with the North Pole, meaning it will spin itself until it faces North. (Make sure you remind/show students which way is North in relation to your classroom. Use a compass. If you can, use masking tape or painter’s tape to “draw” the North/South axis on the floor). Once the magnet has settled, have the students twist the string so the “north side” is facing south. They can then see if it will twist itself until it faces north again. It should! Now they know they can label this side “north” and the other side “south.” See the demo video. The link to the video is on THINK Train. Give youth a 5 minute clean-up warning. Debrief: Ask these questions to check for understanding: 1. Shout outs now! Complete this sentence. Every magnet has a ______________ (north pole) AND A _____ (south pole!) 2. Rule #2: Two like poles will what? (Repel one another, push each other away) 3. Rule #3: Two unlike poles will what? (attract one another, pull toward one another) 4. So a north pole meets a south pole. Do they attract or repel? (Attract!) 5. A south pole meets a south pole. Attract or repel? (Repel!) 6. A south meets a north pole. Attract or repel? (Attract!) 7. A north pole meets a north pole. Attract or repel? (Repel) 8. A west pole meets an east pole. Attract or repel? (Huh? What?) Gotcha! Just checking if you were all awake! 9. The north pole of a magnet will always try to face in what direction? (North) 7 Tips/Things that work well/Resources: 1. Go to THINK Train for a link to the training videos for this activity. 2. This is where the north and south poles are located on the two types of magnets we sent you: 3. Each PL should have received a pre-labeled magnet at the training. If not, see your QAC. We can send them a pre-labeled magnet with directions on how to label other magnets in your kit. 4. At the end of this lesson, do not remove the north and south labels from the magnets. You will need labeled magnets for Lesson 4. 8 MAGNETS Lesson 3 Group Grade(s) 4&5 Week Day Materials/Equipment: Paper—divided into two columns Pencils 2 Magnets per group (It’s ok if these magnets still have the N/S labels on them from Lesson 2) 1 quart size Ziploc bag per group Water (about 2 cups per group, have extra on hand just in case) ¾ cup Total Cereal per group (It must be Total cereal; other brands will not work.) Optional: ¾ cup of another brand of cornflakes that has less iron than Total Eating Iron for Breakfast Handout Activity Name: Scavenger Hunt & Eating Iron for Breakfast Rotation or Session # 3 of 8 Goal/Objective of Activity: Goal: The purpose of today’s lesson is to think about how magnets are used in everyday life. Objective: Students will be able to name everyday objects that use magnets and everyday objects that are attracted to magnets. Background Information for the Teacher: Magnets are useful in our daily lives. Every electric motor has a magnetic field. We saw them used in a compass. But magnets can also be used to hang up refrigerator art and as part of the brakes for a roller coaster. Power locks are magnetic, door bells have a magnet in them, microwaves, refrigerators white boards and earrings (and other jewelry) also have magnets in them. Today’s lesson is going to focus on identifying practical uses of magnets and also completing a Scavenger Hunt to find 10 things that are attracted to magnets and 10 things that are not attracted to magnets. Safety Note: Make sure you keep kids in your line of sight as they perform the scavenger hunt. Make sure they know where they can and cannot go (for example, do not open a teacher’s drawers). Make sure they do not climb on anything. Make sure they do not put the magnets anywhere near a computer, cellphone, or wallet as they can damage hard drives and magnetic strips on credit cards. 9 Activity Instructions: Opening: 1. Ask students to think of everyday items that use magnets and/or practical uses for magnets. Ask kids to share out (share out tips below). Possible answers include sliding drawers, cabinet doors, fridge magnets, jewelry clasps, laptop cases, etc. Also, they should remember that compasses use magnets! 2. Explain that you will perform a scavenger hunt today where you will try to find as many items as possible that are attracted to magnets. Review what types of items are attracted to magnets. Magnets are attracted to ferromagnetic metals, mainly iron, nickel, and cobalt. From Lesson 1, we learned that most ferromagnetic items we’ll encounter in our everyday lives are made of iron and steel. We rarely encounter nickel and cobalt in everyday items. 3. Explain that after the Scavenger Hunt, they will perform a demonstration where they will use a magnet to locate iron in a surprising everyday item: cereal. Yes, cereal! What you will do: 1. Divide students in to groups of 4 for the Scavenger Hunt 2. Distribute a piece of paper and ask them to fold into two columns, labeling one column Attracted and the second column Not Attracted 3. Give each group 2 magnets 4. Instruct them to circulate through the room and find 10 things that are attracted to magnets and 10 items that are not attracted to magnets. If you have access to areas other than classroom space, have children check out a variety of areas. 5. Explain that they will have 15 minutes to complete the list of items and that the groups will come back together and share out the items on the list. As the first group reads his/her list, the others will mark off the items that are on the list they made, calling out so the first group can mark the item off as well. At the end, the group that has the most items left will win. 6. Complete the activity. 7. Once youth have completed this activity explain that they will now be given another activity involving Total cereal. 8. Explain that they will see if there is anything in Total cereal that will be attracted to the magnet. 9. Distribute the Eating Iron for Breakfast handout to the groups. Give demonstration materials to the groups. Circulate and help them find the iron pieces in the cereal. 10. Give youth a 5 minute clean-up warning. Note: There should be small iron filings that will be attracted to the magnet. The iron pieces are an example of ferromagnetic materials (fancy term for materials attracted to magnets). The most common material in nature that exhibits ferromagnetic properties is iron. 10 Debrief: Ask these questions to encourage reflection: 1. Which things today were a confirmation of what you already knew? (They will probably bring up similar findings from the first lesson…magnets are attracted to some metals, mostly steel items in the classroom. Magnets are not attracted to glass, wood, plastic, fabric, etc.) 2. What was surprising or caused you to tweak your thinking? (The cereal! That’s crazy! The iron pieces are ferromagnetic. Doctors encourage us to get enough iron in our diet by eating things like spinach, which have naturally occurring iron in them, but we don’t really think of finding tiny pieces of iron in our cereal. Who knew? But make sure you tell the students that they should NOT go around trying to eat small pieces of iron! This is something food scientists figure out with very careful testing.) Tips/Things that work well/Resources: 1. You should really try out the cereal experiment on your own, ahead of time. It’s a little tricky. You can see step by step photos of the experiment here: http://www.stevespanglerscience.com/lab/experiments/nails-for-breakfast 2. You must buy Total brand cereal in order for the activity to work. It is one of the few brands with 100% daily serving of iron. In order to make the activity into an experiment, you can buy another brand of cornflakes with a smaller percentage of daily iron servings and perform the same test. 3. For the “Opening” share out, you can use any of the following techniques: Use shout outs and record answers on the board. Give each student a Post-It note and have them write an answer and silently stick it on the board. You would read out the answers out loud afterward. For white boards, have several white board pens laid out. Ask students to silently come up and write their answers on the board. You do not need to call on them. They can come up in multiples. You would read out and clarify answers afterward. All of the above techniques encourage as many students as possible to respond to the question in a short amount of time. 11 MAGNETS Lesson 4 Group Grade(s) 4&5 Week Day Materials/Equipment: For making temporary magnets: Whole paperclips. Use the small ones that are 1 ¼ inch long. (6-8 per group of 4) A Sharpie (1 per group of 4) Magnets that are pre-labeled with “north” and “south” poles (2 per group of 4, the shape does not matter). Hopefully, you still have the labeled magnets from Lesson 2. If not, you’ll need to use your pre-labeled magnet to re-label the magnets for the students. Just use the “opposites attract” rule and you should be fine. For making a compass: Plastic bottle cap or lid, about 1.5” - 2” in diameter (1 per group of 4). If you can’t find enough plastic bottle caps, you can cut the bottom off of a plastic cup, leaving the sides ¼” high. Test them to make sure they float. Small paperclip stretched out straight, clipped to 3” long if necessary(2 per group of 4). Use wire cutters and safety goggles to prepare these. Make them ahead of time for the students. Plastic bowl or paper bowl (1 per group of 4) Water (2 cups per group of 4) One real compass for the whole class, if possible. If not, you can download/use a compass app on a smart phone. Note: The teacher will need a set of all materials in order to model the process Activity Name: Turn Paperclips into Temporary Magnets and Build Your Own Compass Rotation or Session # 4 of 8 Goal/Objective of Activity: Goal: The purpose of today’s lesson is to review the 2 poles of a magnet (north and south) and to introduce students to the concept of temporary magnets. Objective: Students will be able to name the two poles of a magnet. Students will be able to explain how to turn an object into a temporary magnet. Students will be able to briefly explain how a compass works. 12 Background Information for the Teacher: All magnets have two poles: a north pole that is attracted to the earth’s North Pole, and a south pole that is attracted to earth’s South Pole. Two unlike magnetic poles (north + south) always attract each other, but pairs of like poles (north + north OR south + south) always repel or push each other away. Magnets always have two poles, even when broken into small pieces. No-one knows how this happens, but we do know that opposite magnetic poles attract and like poles repel. Magnets occur naturally, but certain metals can be induced to become temporary magnets. The simplest way is to stroke an item containing iron in a single direction with a magnet. This will cause its magnetic domains to line up facing the same direction, and the item will act like a magnet until those domains move around and are no longer lined up. In today’s lesson, youth will make a compass using this temporary magnetic “needle.” Activity Instructions: Opening: 1. Ask students to review what they learned about magnets during the last few lessons. Magnets are usually made of iron. They have magnetic fields that can attract other items mostly metal items containing iron, nickel, cobalt (and steel, which is a metal alloy made mostly of iron). Magnets have a north pole and a south pole. Like poles repel and opposite poles attract. The north pole of a magnet will always try to point North, and the south pole of a magnet will try to point South. 2. Ask students if they know what a compass is and what it’s used for. Tool used to find one’s way or navigate. The needle always points North. 3. Explain that the earth has a north magnetic pole and a south magnetic pole. Magnets also have a north pole and a south pole, which we learned in Lesson 2. Again, a magnet’s north pole is attracted to the earth’s North Pole and its south pole is attracted to the earth’s South Pole! That’s how compasses work. The needle is magnetic, so the needle’s north pole always points North. 4. Ask students if they think you can turn an object into a magnet. If they answer yes, ask them how they think you would do it, and ask them what types of materials they think could be turned into a magnet. 5. Explain that you can use a permanent magnet, like the magnets they’ve been using, to turn some metal objects into temporary magnets. Tell the students that today, they will be turning paperclips into temporary magnets. They will then use this trick to make a compass! What you will do for Activity 1 – Turning Paperclips into Temporary Magnets: 13 Magnetize several paperclips to see the positive and negative ends attracting. 1. Have materials set up for each group and materials set up for you up front. 2. Divide youth into groups of 4. You will be modeling the activity for the students. 3. Have them color the tip of the paperclips with a Sharpie. The colored tips will be the north pole. The uncolored ends will be the south pole. 4. Have them watch you as you perform the next step. 5. Pick up one of the pre-labeled magnets. Stroke the paperclip with the north side of the magnet very quickly for about 30 seconds (or 50 strokes). It is important that you pick up the magnet in between strokes and only go in one direction: toward the north tip of the paperclip. Again, do not rub it back and forth. Stroke the paperclip in one direction. 6. This should cause the atoms in the paperclip to align in one direction. It will become a temporary paperclip. Quickly do the same thing with a second paperclip. 7. Show the kids that you can now use one of the paperclips to pick up the other paperclip. Make sure you are using a north end to pick up a south end of a paperclip (opposites attract). Hold it up delicately as the magnetism won’t be that strong. 8. Now, have the students do it themselves. Two students can magnetize paperclips at the same time and then see if the paperclips will stick to each other. 9. Have students switch roles so that each student has a chance to magnetize a paperclip. What you will do for Activity 2 – Making a Compass: 1. Hand out the compass materials for each group, and again, have materials set up for you up front. 2. Have students stay in their groups of 4. You will be modeling this activity for the students. They will make their compass as you make your compass. You will be narrating and modeling the following steps. 3. Explain that today they are going to create a compass by using a straightened paperclip, a magnet, a small plastic lid, and a small bowl of water. Hold up each item. Have students make sure they have each item. Try to get a real compass for comparison purposes, or use your smart phone compass app. They can check their compasses with your compass/phone when they’re done. 4. Hold up the straightened paperclip. Take a magnet and stroke the paperclip with it for 30 seconds. Make sure you are stroking the paperclip in one direction, just as you did when you were creating your temporary magnets. Tell the students that you are doing the same thing here turning this straightened paperclip into a temporary magnet. 5. Take the plastic lid, flip it upside down. Place the paperclip on the plastic lid. Then gently place the lid in the bowl of water. It should float. 14 6. The now-magnetized paperclip will orient itself in a north/south position. You have created your own compass. To test this, you can turn the cap until you know that the “needle” is facing east/west and watch as it turns itself back to the north/south position. Or, you can spin the bowl. The needle and cap should stay still (pointing north) even as the bowl spins around it. Give youth a 5 minute warning and then clean up and close the activity with the review, reflect, and debrief. Debrief: Ask these questions to check for understanding: 1. What’s a compass? (helps you find your way) How? (It always points north) How does it work? (The needle in a compass is a magnet!) 2. Finish this sentence: All magnets have two _______________. (poles) 3. What are the poles called? (north and south) 4. A magnet’s north pole is drawn to what? (the earth’s North Pole) 5. True or false? A magnet will always have a north pole and a south pole, even if you cut it in half. (true) 6. True or false? The earth has its own magnetic fields. (true) 7. What is a temporary magnet? (It’s when you use a permanent magnet to give an object magnetic qualities. The magnetism doesn’t last long.) Ask these questions to help students reflect: 1. What was your favorite part of this activity? Why? 2. What was one Aha! moment you had today. Did anything surprise you? Tips/Things that work well/Resources: Try this at home before you do it in class. A description and pictures of the experiment can be found at numerous sites, including here: http://www.physicscentral.com/experiment/physicsathome/compass.cfm 15 FYI: If you feel super comfortable with the subject matter, you can go deeper into compass activity. You can actually color either the north or south pole of the paperclip with a red Sharpie. Pay attention to which pole of the actual magnet you’re using to magnetize the paperclip (for example the north side) and which direction you’re stroking it in. Knowing that unlike poles attract, you should be able to predict whether the colored end of the paperclip will point North or South. It’s a bit confusing and takes a few practice sessions to wrap your head around it. But if you can teach it to yourself, it would be super fun to then show it to the students and have them do the same. You can also see our training video. The link is on THINK Train. 16 MAGNETS Lesson 5 Group Grade(s) 4&5 Week Day Materials/Equipment: Wooden pencils (1 per group of 4) 2 ring magnets per group of 4. It does not matter if these magnets are pre-labeled or not. If you leave the stickers on from previous lessons, that’s fine. You must use ring magnets for this activity. Bar magnets will not work. If you do not have enough ring magnets in your kit, alternate days with another PL at your site so you can combine your ring magnets. 3” x 5” cards (1 per group of 4) String (about 1 foot long piece per group of 4) Paper Clip (2 per group of 4) Magnet Challenges Sheet for each group of 4 Activity Name: Magnet Challenges 1-6 Rotation or Session # 5 of 8 Goal/Objective of Activity: Goal: The purpose of today’s lesson is to ensure that students understand the concept of repulsion and attraction and that like poles repel and opposite poles attract Objective: Students will be able to understand how to use the attraction and repulsion of magnets to complete certain tasks. Background Information for the Teacher: Background Information: All magnets have two poles; a north pole that is attracted to the Earth’s North Pole, and a south that is attracted to Earth’s South Pole. Unlike magnetic poles (north + south) always attract each other, but pairs of like poles (north + north OR south + south) always repel or push each other away. Magnets always have two poles, even when broken into small pieces. No-one knows how this happens, but we do know that opposite magnetic poles attract and like poles repel. Here is another way to explain the same phenomena. When you bring two magnets close together, the magnets each exert a magnetic force on the other. These magnetic forces result from spinning electric charges in the magnets. The force can either push the magnets apart or pull them together. The magnetic force is a universal force. It is always present when magnetic poles come near one another. Think of the last time you worked with magnets. If you held two magnets in a certain way, they pulled together. When you turned one of the magnets around, they pushed apart. Why? The magnetic force between magnets depends on how the poles of the magnets line up. Like poles repel, and opposite poles attract. Understanding the concept above (first shared in lesson 2 and then again in lesson 4) is key to doing the “magic” in today’s lesson. Review this information. Be sure the youth are using words like attract and repel to discuss how magnets interact with other magnets. 17 Activity Instructions: Opening: Let’s review some rules for magnets from the last lesson: 1. All magnets have a north pole and a south pole. 2. Like poles repel one another. 3. Unlike poles attract one another. Opposites attract! Magnet Challenges 1-6 What you will do: 1. Review safety rules for these magnets: Perform the tricks today over the table top. Sit up straight as you do the tricks. Do not lean in close to the magnets. Do not put them close to your face. Observe from a safe distance. 2. Explain that today they will have several challenges to complete to reinforce understanding of the information discussed. 3. Divide youth into groups of 4. 4. Distribute the materials listed above to each group. 5. Give each group an opportunity to work through the challenges. 6. Bring groups back together to discuss what happened with each challenge. 7. Ask youth to vote for the challenge they most enjoyed. Give youth a 5 minute clean-up warning. Debrief: Share out the findings from their challenges. Here is a little answer sheet for you: Challenge #1. Hold a pencil upright. Place one ring magnet on the pencil (through the hole). Place the other ring magnet on top of it, making sure that the two LIKE sides are facing each other. Because like sides repel, the magnetic forces will keep the top magnet from touching the bottom magnet. It will look like it’s floating. Challenge #2. Hold the two magnets tightly together in your hand so that two like sides are facing inward. It will be hard since they will try to repel each other. You will feel the push. Let go of the top magnet. The force of the repelling magnets will push the magnet off so quickly that it looks like it’s jumping! Challenge #3. Again, we’re using the repelling force of two like sides. Put one ring magnet on the tabletop. Hold the second ring magnet so that the like side is facing the magnet on the table. Get closer until the repelling force starts pushing the magnet on the table. You can chase it around this way! 18 Challenge #4: Put a magnet on top of the index card. Put a magnet underneath the card right below the other magnet. The unlike sides should be facing inward so that that magnets are sticking together. Then, you can move the magnet on the bottom so it looks like the top magnet is moving on its own. Magic! Challenge #5: Put one magnet north side down. Put one north side up right next to it so the rims are touching. Carefully pick up one magnet. The other magnet should roll along the edge of the first one. Try it with the like poles facing the same way. It won’t work! Challenge #6: Tie a piece of string to one magnet. Tie a paperclip at one end. Take the other magnet and use it to pick up the paperclip. Pull upward until it looks like the string is standing straight up (sort of) by itself! Okay, this one doesn’t work too well, but it’s still worth a try. Tips/Things that work well/Resources: Do these tricks yourself. They’re super fun! There is a training video for this activity on THINK Train. 19 MAGNETS Lesson 6 Group Grade(s) 4&5 Week Day Materials/Equipment: Paper clips (a small handful per group) 2 Bar magnet per group 2 Ring magnets per group “What is the Strongest Section of the Magnet?” Handout Note: Some of you may not have enough bar magnets and ring magnets to have all the groups performing the lab at once. You can have half the groups test out the bar magnets first while the other half tests out the ring magnets. Then they can switch. Other sites only received ring magnets due to purchasing issues. You can only do the ring magnet part of the lab. Apologies! Activity Name: Strongest Section of a Magnet Lab Rotation or Session # 6 of 8 Goal/Objective of Activity: Goal: The purpose of today’s lesson is to determine if sections of a magnet have a stronger pull or magnetism than other sections. Objective: Students will be able to carry out multiple trials in an experiment format. Background Information for the Teacher: A magnetic field is strongest close to the magnet and gets weaker as the distance from the magnet increases. The stronger the magnet, the further away its magnetic field can be felt. Magnetic field can even pass through paper, plastic, or glass. The lines of magnetic force extend from the magnet’s ends, or poles, in all directions, including side-to-side and upward and downward. The magnetic effects are not the same throughout a magnet. What would happen if you dipped a bar magnet into a box of paper clips? Most of the clips would stick to the ends of the bar, as shown the picture below. This shows that the strongest effects are near the ends of the bar magnet. Each end of the magnet is a magnetic pole. As you will see, magnetic poles are points on a magnet that have opposite magnetic qualities. The experiment for the youth today is to determine which part of the magnet will hold the most paper clips, so don’t share this information with them until AFTER the experiment. Hopefully they will already know this. Activity Instructions: Opening: Go ahead and read the background information (first whole paragraph) to the students. Then jump 20 right into the activity! Strongest Section of a Magnet What you will do: Investigation #1 Post this question: Which part of the bar magnet will hold the most paper clips? Explain that youth will work in pairs or teams of 3 and their task will be to answer the question posed above. Explain that they will follow a specific procedure when verifying the answer to these two questions. Step #1: Predict or Hypothesize about which part of the magnet will hold the most paper clips. Write down your prediction or hypotheses by stating: The ___________ of the bar magnet will hold the most paper clips. Step #2: Before doing any experimenting, make a plan about how you will test your hypothesis and how you will record your data. Write it down so you know everyone is on the same page. Example: We predict the middle of the bar magnet will magnetize the most clips. Our plan is to divide the magnet into three sections (end 1, middle, end 2) spread the paper clips out over a flat surface and then put Example the magnet down in the clips and then Trial End 1 Middle End 2 slowly lift it up and count the number of 1 8 5 9 paper clips in each section. We will do 2 9 3 9 the experiment 3 times and record the data 3 10 2 8 on a chart and then calculate the average. Average 9 3.3 8.8 Step #3: Complete the experiment three times as you laid it out in Step 2, each time record the number of paperclips the magnet held on each part of the magnet. Step #4 Determine the results of your experiment record the information in your table Step #5: Explain why your predication/hypothesis was either accurate or inaccurate. Example: Our hypothesis was not correct. More clips were magnetized by the ends. It didn’t matter which end, the ends were more magnetic that the center. We believe that this is because the ends are where the north and south poles are strongest and therefore the magnet is strongest there. Bring class together to share results. Investigation #2 21 Now post this question: Which part of the ring magnet will hold the most paper clips? The __________________ of the ring magnet will hold the most paper clips. 1. Discuss three places that they could check on the ring magnet (inside edge, outside edge, flat surface.) 2. How might they check (make one clip a hook and then attach others to the hook and see how many it would hold). Encourage youth to consider what they learned with the bar magnet. 3. Distribute ring magnets—repeat steps above 4. Bring class together to share results. Give youth a 5 minute clean-up warning Debrief: Go over the results/findings of each investigation as a whole group. Tips/Things that work well/Resources: If you want, you can show students how to have a more accurate reading of how many magnets can be held by certain areas of a magnet. They can unfold one paperclip and turn it into a hook. They then stick it on the part of the magnet in question. Then, they can systematically hang paperclips one by one during the trials. 22 MAGNETS Lesson 7 Group Grade(s) 4&5 Week Day Materials/Equipment: SAFETY FIRST! YOU MUST FOLLOW ALL SAFETY PRECAUTIONS WITH THIS ACTIVITY! One iron or steel bolt, about 2-3” long for each team of 4. If you’re uncertain about what kind of bolt to buy, bring a magnet with you when you go to the store. If the magnet sticks to the bolt, the bolt should work in this activity. 30 inches of 22-gauge insulated copper wire for each team of 4. You can buy CerroWire Bell Wire. It’s different than what we used in the training/demo videos, but it works even better and the pvc coating is safer for everyone. Also, it’s easier to find. It can be purchased at Home Depot. We will try to send you some, but if we can’t, here is a link to the item: http://www.homedepot.com/p/Cerrowire-65-ft-20-2-Bell-Wire-206-0101BA3/202304706?keyword=copper+bell+wire Since this wire has a plastic coating, you will need to strip 2” of coating off each end of the strip. Prep these ahead of time. You do not need to buy wire strippers to strip the coating off. We used regular scissors and it worked well. Just do it slowly so you don’t cut through the copper wire. Because this is a different type of wire, you do not need to buy nail files for the students. Have them skip that step on the handout. Note: While the pvc coating makes the wire a little safer, the exposed copper wire at the ends still gets very hot. You still need to wear gloves and avoid touching the exposed ends of the wire once they’re attached to the battery. Keep these wires. You can reuse them tomorrow. 1 D-cell (1.5 volt) batteries for each team of 4 (You’ll need another one tomorrow. They run out quickly.) 20 small metal paper clips for each team (#1 size) 6 strips of painter’s tape, about 2” each, ready to go at each station. Have the roll available just in case. Pen or pencil Building an Electromagnet handout Pair of latex lab gloves for each student SAFETY FIRST! YOU MUST FOLLOW ALL SAFETY PRECAUTIONS WITH THIS ACTIVITY! Activity Name: Make an electromagnet Rotation or Session # 7 of 8 Goal/Objective of Activity: Goal: The purpose of today’s lesson is to build an electromagnet and discover how they work. Objective: Students will be able to explain the difference between a temporary magnet, a permanent magnet, and an electromagnet. Background Information for the Teacher: 23 Sometimes we need magnets whose strength can be more easily regulated and/or can be turned on and off when needed. Electromagnets allow us to do this. An electromagnet is a magnet that runs on electricity. Unlike a permanent magnet, the strength of an electromagnet can easily be changed by changing the amount of electric current that flows through it. The poles of an electromagnet can even be reversed by reversing the flow of electricity. An electromagnet works because an electric current produces a magnetic field. The magnetic field produced by an electric current forms circles around the electric current, as shown in the diagram below: If a wire carrying an electric current is formed into a series of loops, the magnetic field can be concentrated within the loops. The magnetic field can be strengthened even more by wrapping the wire around a core. The atoms of certain materials, such as iron, nickel and cobalt, each behave like tiny magnets. Normally, the atoms in something like a lump of iron point in random directions and the individual magnetic fields tend to cancel each other out. However, the magnetic field produced by the wire wrapped around the core can force some of the atoms within the core to point in one direction. All of their little magnetic fields add together, creating a stronger magnetic field As the current flowing around the core increases, the number of aligned atoms increases and the stronger the magnetic field becomes. At least, up to a point. Sooner or later, all of the atoms that can be aligned will be aligned. At this point, the magnet is said to be saturated and increasing the electric current flowing around the core no longer affects the magnetization of the core itself. Activity Instructions: Opening: Go ahead and share a summary of the background info to the students. Then, GO OVER SAFETY REMINDERS. Everyone must be clear about the safety rules for this lesson. Read these rules to the students and follow them yourself!: 1. You must wear gloves during the experiment. 2. Once the bolt and wires have been taped to the battery, do not touch the bolt or wires. They can get hot very quickly. 3. Use painter’s tape or masking tape to hold the wires on the end of the batteries. The plastic-covered area of the battery and taped areas are the safe areas to touch. You still need to wear gloves, though. 4. As soon as you’re done with the test, take apart the electromagnet (detach the wire from both ends of the battery). Otherwise, the wires will drain the charge from the batteries in a manner of minutes. 5. PLs- Make sure all wires/bolts have been detached from the batteries before you store 24 items. What you will do: SAFETY FIRST! SAFETY FIRST! SAFETY FIRST! Note: This activity works best on tables that are large enough for the entire team to work around. 1. Divide the class into teams of 4 per group. 2. Distribute one set of materials to each team. Have students put on their latex gloves. 3. Explain to the youth that they will need to follow the directions for building the electromagnet as you give them. They will also have a handout at their table to look at. You should still walk them through it, though. The more clear the instructions are for this experiment, the better. (tomorrow they will get to investigate more on their own) 4. Strip 3-5 cm (1-2 in.) of the varnish coating from both ends of the wire. It may be rubbed off with an emery board or nail file. Be careful not to rub the wire too hard or it will break. The students can skip this step as you are now using the pvc coated wires that you have already stripped for them. We don’t want you to waste copies of the pre-printed student handout, however, so verbally tell them to skip this step. 5. Wrap the wire in tight, even coils around the bolt. Tell them to be sure to leave at least 3 or 4 in. loose at each end of the coil so they can connect the wires to the batteries. 6. Connect one end of one wire to the positive (+) end of one of the batteries, and then connect the other wire end to the negative (-) end of the other battery. Tape the wires down tight with masking tape or painter’s tape. At this point, warn them the ends of the battery and the wire can get hot, so they should only touch middle of the battery or the section covered in painter’s tape when they’re holding it. 7. Ask youth how they know if their electromagnet is working. Tell them to test their electromagnets by trying to pick up one of the paper clips with the wire-wrapped bolt. 8. If the electromagnet is working, it will be magnetic and able to attract and hold a paper clip. If it does not work, ask them what things they might want to check: 9. Make sure all the connections are tight 10. That the batteries are not dead 11. That the coils are wrapped tightly around the bolt. 12. Encourage youth to adjust their electromagnet’s construction as needed and try again until it works successfully. 13. Teams should complete the instructions and answer the questions on page 2 of the handout 14. Note: The electromagnet will not become magnetized unless both ends of the wire are connected, and the bolt will not be able to pick up any paper clips. It is possible that after the electromagnet has been magnetized, it may retain its magnetism for some time after it is disconnected from the battery. 15. Give teams the 5 minute warning for clean-up. Make sure the electromagnets are taken apart! Bring group back together to discuss the team experiences. Debrief: Go over the questions on the Electromagnet Data Sheet. Tips/Things that work well/Resources: 25 FOLLOW ALL SAFETY PRECAUTIONS! The less time the wires stay attached to the batteries, the better. The process drains the batteries fairly quickly. You definitely need new batteries for the next lesson. Demo video link is on THINK Train. 26 MAGNETS Lesson 8 Group Grade(s) 4&5 Week Day Materials/Equipment: SAFETY FIRST! YOU MUST FOLLOW ALL SAFETY PRECAUTIONS WITH THIS ACTIVITY! One iron or steel bolt, about 2-3” long for each team of 4. If you’re uncertain about what kind of bolt to buy, bring a magnet with you when you go to the store. If the magnet will stick to the bolt, the bolt should work for this experiment. 30 inches of 22-gauge insulated copper wire for each team of 4. You can buy CerroWire Bell Wire. See the materials list in Lesson 7. 1 D-cell (1.5 volt) batteries for each team of 4 20 small metal paper clips for each team (#1 size) 6 strips of painter’s tape, about 3” each, ready to go at each station. Have the roll available just in case. Pen or pencil Pair of latex lab gloves for each student Magnets Post-Assessment Test Activity Name: More electromagnet challenges Rotation or Session # 8 of 8 Goal/Objective of Activity: Goal: The purpose of today’s lesson is to solidify the learning about magnets that has occurred over the past 7 lessons and to complete the Post-Test. Objective: Students will be able to name what objects magnets attract, name the two poles of a magnet, name which poles attract and repel each other, and explain the difference between permanent magnets, temporary magnets, and electromagnets. Background Information for the Teacher: Background Information: Magnets attract, or pull, some kinds of metal objects. Stronger magnets exert a greater pull on the objects they attract. Sometimes it would be useful if you could "turn off" a magnet when you did not want it to attract objects. That is what an electromagnet can do. Some electromagnets --- like those used in power plants and factories --- are very large. You can make a small, simple electromagnet in an afterschool program with a battery. How It Works Electric current can act like a magnet: it attracts objects made of certain metals, such as iron. When electric current flows through a wire, it generates a magnetic field. Coiling the wire strengthens the magnetic force. This coil is called a solenoid. The magnetic field produced inside the solenoid is an electromagnet. The strength of this electromagnet increases when a 27 core of magnetic material, such as iron, is placed inside the solenoid. Unlike the magnet that holds a piece of paper on a refrigerator, an electromagnet is a temporary magnet. It exerts a magnetic force only while electricity flows through it. Electricity is necessary to make electromagnets push or pull magnetic objects. When the circuit is closed, the flow of electricity stops and the electromagnet releases the object. Uses We use electromagnets every day. Doorbells, speakers and electric motors are some common applications of electromagnets. Electromagnets are used to generate electricity in power plants and pick up cars at junk yards. Maglev trains use magnets to hover above the rails without wheels. These trains run very smoothly at speeds up to 300 miles per hour. Benefits We can control the magnetic energy of electromagnets by turning their magnetic fields on and off. For example, large electromagnets can attract large objects such as cars or turbines. When the current flowing to the electromagnet is turned off, the electromagnet can release the car or stop turning the turbine. If a doorbell contained a permanent magnet instead of an electromagnet, the bell would continue to ring even after you stopped pushing the button. Yesterday youth built an electromagnet using batteries, wires, and bolts. Today, youth will be challenged to answer additional questions about electromagnets. Activity Instructions: More Magnet Challenges What you will need: SAFETY! SAFETY! SAFETY! Read these rules to the students and follow them yourself!: 1. You must wear gloves during the experiment. 2. Once the bolt and wires have been taped to the battery, do not touch the bolt or wires. They can get hot very quickly. 3. Use painter’s tape or masking tape to hold the wires on the end of the batteries. If you need to hold the battery, touch the taped areas or plastic covered areas only. 4. As soon as you’re done with the test, take apart the electromagnet (detach the wire from both ends of the battery). Otherwise, the wires will drain the charge from the batteries in a manner of minutes. 5. PLs- Make sure all wires/bolts have been detached from the batteries before you store items. What you will do: 1. Divide the group into the same teams as yesterday. Give them the same materials from yesterday (Replace anything that was destroyed; make available twice as many batteries and masking tape, you will not need the handout) 2. Explain that today they will be asked to use the information from the past lessons to accomplish the challenges of today. Challenge #1: Make a stronger electromagnet than you made yesterday. Be prepared to discuss what you did and how you know it is stronger today than yesterday. 28 Note for instructor: This can be done by adding another battery or increasing the number of coils wrapped around the bolt. Challenge #2: This challenge is about which magnet you would select to do a particular task. The magnet selections are “temporary”, “permanent”, and “electromagnet”. Youth are to create a list of tasks that are better done with magnets and then decide which type of magnet would work the best and why. See sample following: Temporary Picture on a refrigerator could be held by a temporary magnet, although the closing of the door could be problematic Permanent Latch on a door that tends to swing shut. The permanent magnet would be important so the door could stay open every time by connecting to the permanent magnet. Electromagnet Doorbell—you need it to work every time the electrical circuit is completed—not permanently and not randomly or temporarily. In place of Challenges #1 and #2, you can review what you’ve learned during this unit. This might be a good option if the electromagnet activity was particularly stressful for you or if you don’t have enough supplies. IMPORTANT: At the end of the lesson bring the youth back together and give the Post-Assessment Test—the same five questions that were given at the beginning of the investigation into magnets. Record the answers next to the youth’s name and his/her first score. If you use Survey Monkey this will be done for you. Debrief: Students should share out their findings from the challenges. You should also do a mini-review of the main magnets concepts/ideas. If you want, you can also use this debrief session to introduce the science fair. Tips/Things that work well/Resources: 29