Download Session E

Science Year 3
Biology Strand: Animals, including humans
This plan makes reference to session resources that can be downloaded at https://www.hamiltontrust.org.uk/browse/science/y3/animals-including-humans-year-3-new-currriculum/86880.
Session E
Compare skeletons
Programme of study: Identify that humans and some other animals have skeletons and
muscles for support, protection and movement
Record findings using simple scientific language & labelled diagrams
Set up simple practical enquiries
Gather and record data in a variety of ways to help in answering questions
Exoskeleton examples, e.g. snail, crab shell if available, visit to local museum (optional),
Resources needed collection of sterilised bones (chicken, fish, lamb, rabbit), trays of sand, hand lenses, sketching
pencils, drawing paper, access to the internet
Whole class teaching: (links to Session 5, Citius Altius Fortius Theme, LKS2 Olympics Topic)
Remind children of the functions of the human skeleton – protection, support, movement and revise the scientific
names learnt in the previous session. Tell the children that humans share many common characteristics with other
animals including skeletons. Explain that not all animals have their skeletons inside their bodies (internal or
endoskeletons) – vertebrates, e.g. armadillo & tortoises have an endoskeleton & exoskeleton & invertebrates, e.g.
insects, crabs, have exoskeletons. See http://www.bbc.co.uk/learningzone/clips/invertebrate-skeletons/2304.html.
What functions do these external skeletons have? – Protect the softer insides, give structural support to the organs &
muscles & facilitate movement of limbs (same as endoskeletons!). Discuss how some animals with exoskeletons need
to moult (shed) their exoskeleton & replace it so that they can grow, e.g. lobsters. Explain how the new exoskeleton is
soft & pliable to start with & the animal pumps itself up using air or water to stretch the exoskeleton to maximum size
before it hardens. Some other animals shed their skeletons completely before finding another, e.g. hermit crab! Other
animals grow their shell at the opening as they grow (e.g. snails). Show some examples of exoskeletons if available.
Working
scientifically
Group activities:
Adult-led activity: At this point you may wish to arrange a visit to your local museum many of which exhibit bones and
fossils. If this is not possible you may want to make a collection of bones which have been sterilised (should be
handled with gloves) – chicken, fish, lamb, rabbit, etc. Bury the bones in trays filled with sand and allow the children
to slowly uncover the bones like archaeologists or palaeontologists. Can they identify the animal from the size or
shape of the bones what they are uncovering? Do the bones belong to a four-legged creature or a winged animal for
instance? Take a close look at the bones. Encourage children to describe the bones – hard, strong, light, smooth, rigid
– why is each of these characteristics important? They should use hand lenses to look closer – can children see where
muscles are attached? What do they notice about the shape of them? – They tend to be larger at the joints. Look at
joints – how bones slide/move over/against each other (more later – Session E). Children should make detailed
observational drawings of the bones – which can then be annotated.
Place images of other skeletons and bones in the trays for the children to uncover (session resource). Can they identify
the animal that it belongs to? Ask the children to stick the picture of the skeleton in their books and to annotate it
with the name of the creature they think that it belonged to; they should also describe the clues that lead them to
that conclusion – body shape, teeth in the skull, number and length of limbs, etc.
Individual activity:
Following on from the adult-led activity allow the children to play the Mammal Maker game at
http://pearl.tvb.com/lifeofmammals/challenges/flash/maker.swf - there they find out that mammals have very
different bodies and that their skeletons are adapted to suit their lives. Explain that animals adapt over time to
become better suited to their environment, e.g. legs have become flippers for sea living mammals, giraffes have
adapted to have long legs and necks to reach the leaves on the tallest trees.
Individual activity:
Children can build mammal skeletons from fossils found by archaeologists at (there are three levels)
http://www.bbc.co.uk/sn/prehistoric_life/games/skeleton_jigsaw/. Or they can build skeletons at
http://www.rigb.org/contentControl?action=displayContent&id=00000001873. Again children can see how the
skeletons are adapted for the particular animal and yet are similar to human skeletons.
Plenary:
Briefly discuss how archaeologists are often uncovering skeletons in the earth which tell us a lot about creatures that
lived thousands of years ago. The bones which make up skeletons are the last remaining evidence of animals that
once roamed the earth! Relate the properties of bone identified during this session to why they have survived until
today. The skeletons of creatures give us important clues about the way they lived, their diets and habitats.
Summarise what the children have discovered. Which creatures have skeletons most like ours? How are the skeletons
of animals well suited to their habitat, etc? Ask general questions - Do fish have ribs? Have horses got finger bones?
Etc.
© Original plan copyright Hamilton Trust, who give permission for it to be adapted as wished by individual users
We refer you to our warning, at the top of the You Will Need document, about links to other websites
Science Year 3
Biology Strand: Animals, including humans
I can:
1. Use first hand observation and secondary sources to find out more about skeletons.
2. Identify similarities to and differences from the skeletons of humans and a variety of animals.
© Original plan copyright Hamilton Trust, who give permission for it to be adapted as wished by individual users
We refer you to our warning, at the top of the You Will Need document, about links to other websites