Download Multiplication Mania

3rd–5th Grade
Objective
• Students will find the product of a single-digit number
and a double-digit number.
• Students will understand how rearranging the numerals
affects the product of a single-digit number and a double-digit number.
Materials Needed
• Baseball number cards template
• Multiplication Mania reproducible
• Scissors
2
3
x
9
Introduction
Write the problems 23 x 9 and 93 x 2 on the board. Ask students, “Do you notice anything similar about these
two problems? Yes, they both use the same numerals but in different places.” Invite students to make a guess
as to which product will be greater. Give them time to find the answers (23 x 9 = 207 and 93 x 2 = 186).
Then ask students if they can think of different ways to arrange the three numerals so that the product would
be greater than 207 or less than 186. Invite students to use a pencil and paper to work out some possible
problems and their answers (such as 39 x 2 = 78, 29 x 3 = 87, 92 x 3 = 276 and 32 x 9 = 288).
Procedure 1. Before you begin, cut out the baseball number cards, which are labeled with numbers 0–9. Place them
facedown on a desk or put them into a bag.
2. Tell students that you are going to rearrange three number cards to build multiplication problems. They will
need to think about how to arrange the number cards to get the largest or smallest product.
3. Draw three cards and show students the numeral on each card. Ask them to estimate how many different
multiplication problems can be made with the three numerals. Then ask students to help you arrange the
cards to make the problems.
4. Write each problem the students create on the board. Explain the steps aloud as you solve each problem
together.
5. Prompt students to name the two numbers that have the largest product and the two numbers that have
the smallest product. 6. Ask, “How were the three numerals arranged in those problems? Where did we put the largest numeral?
Where did we put the smallest numeral? Do you think the smallest and largest numerals will always have to
be placed in those positions to get the smallest and largest products?” Tell students that you need their help
to find out!
©Lakeshore www.lakeshorelearning.com
Guided/Independent Practice
1. Give each student (or pair of students) a copy of the Multiplication Mania reproducible and the baseball
number cards template.
2. Have students cut out the number cards, then use them to complete the reproducible.
Conclusion:
1. After students are finished, invite them to share the methods they used to find the answers.
2. Ask volunteers to share the problems that resulted in their largest and smallest products. Write them on the board.
3. Discuss whether these problems followed the rule about numeral placement that the class discovered during the lesson.
4. Ask students, “Did anyone use zero as one of the numerals? Which arrangement gave you the smallest
product?” Discuss the fact that the student could have two answers to that question because two of the
possible arrangements result in a product of zero.
Extension Activity
Depending on the skill level of your students, extend this lesson by repeating it with a three- or four-digit number multiplied by a one-digit number. You can also repeat the lesson using a two-digit number multiplied
by a two-digit number.
©Lakeshore www.lakeshorelearning.com
Name:
Directions: Turn the number cards facedown and mix them up. Choose three cards and use them to
complete the steps below.
x
1. Place your cards on the template above to create a multiplication problem. Then write and solve the
problem in the space below. Rearrange the cards to create as many different problems as you can.
2. Which arrangement gave you the largest product?
3. Which arrangement gave you the smallest product?
©Lakeshore
www.lakeshorelearning.com
0 1 2 3 4
5 6 7 8 9
©Lakeshore
www.lakeshorelearning.com