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Chemistry · Early Years · The School
Four things you can do
You can SQUASH something, like a sponge in your hand. You can BEND it, like a pipe cleaner. You can TWIST it, like a wet cloth. And you can STRETCH it, like an elastic band. Some materials let you do all four, and some let you do none of them.
Which materials change
Play dough squashes easily and stays squashed. An elastic band stretches and springs back. A wooden brick will not squash, bend, twist or stretch at all — it just stays as it is. Trying each material and sorting them into what they let you do is proper science, done with your hands.
Springing back
Some things go back to how they were, and some do not. An elastic band springs back. A sponge springs back. Play dough stays in its new shape, and so does a bent paper clip. Both kinds are useful — you would not want a chair that squashed, or a hair band that stayed stretched.
Take a sponge, a rubber band, a lump of plasticine, a piece of kitchen foil and a spring. Change each one's shape, then let go. Sponge, band and spring return to how they were. Plasticine and foil stay changed. Sort them into two piles and name the piles: SPRINGS BACK and STAYS. Now predict which pile a paperclip goes in, and test it — that is a real property, not a guess about how something looks.