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## National STEM Learning Centre

Skip to 0 minutes and 7 secondsSPEAKER 1: All right. So in each of these bags is an object. And one of you is going to pop your hand into the bag, and I'm going to give each pair a bag. And you're going to have a feel around. You're not going to pull the object out yet. You're going to have to feel around. And you're going to try and describe the object that you can feel. How does it feel? As many fabulous, descriptive, scientific words as you can. And then maybe you can start having a think about what it could be without looking though. And you're going to trying to describe to your partner what you think the object might be.

Skip to 0 minutes and 38 secondsSPEAKER 2: So it's soft, like squishy.

Skip to 0 minutes and 45 secondsLINDY: Mine's soft and squishy, but hard at the same time.

Skip to 0 minutes and 50 secondsSPEAKER 2: I think it's like a soccer ball because it's squishy and it's also round.

Skip to 0 minutes and 54 secondsLINDY: It's because it's not that soft. And the outside is a bit hard when you feel it.

Skip to 1 minute and 4 secondsSPEAKER 2: Like, when you, like, squish it, it goes into different shapes.

Skip to 1 minute and 11 secondsSPEAKER 1: Mm-hmm. Does it stay in that new shape?

Skip to 1 minute and 14 secondsSPEAKER 2: So when you're not squish it, it comes like back out as a normal shape.

Skip to 1 minute and 19 secondsSPEAKER 1: Mm-hmm. What do you think it might be used for?

Skip to 1 minute and 22 secondsSPEAKER 1: Go on. You don't have to put your hand up. It's OK.

Skip to 1 minute and 26 secondsSPEAKER 1: You think you might be playing tennis. Why would that be good for playing tennis?

Skip to 1 minute and 30 secondsSPEAKER 3: Because it's a ball. And Lindy's one is quite hard, so it would be kind of like a tennis bell. But instead, it's a bit bigger.

Skip to 1 minute and 38 secondsSPEAKER 1: A little bit bigger than a tennis ball. Do you two want to have a feel of the object as well? Emily.

Skip to 1 minute and 42 secondsEMILY: It would be a good for like, if you want to play catch, and you're really good with a big ball, and you want to have a go with a little ball.

Skip to 1 minute and 50 secondsSPEAKER 1: Ah, why do you think this would be a particularly good ball for that?

Skip to 1 minute and 53 secondsEMILY: Because if you hurt yourself, it wouldn't really hurt.

Skip to 2 minutes and 0 secondsSPEAKER 3: It could be one of those balls where if you're angry with yourself, you squish. And then it makes all of the anger go into the ball.

Skip to 2 minutes and 14 secondsSPEAKER 1: What makes you think it's foam, then?

Skip to 2 minutes and 15 secondsEMILY: Because it's like squishy. And if it was made out of rock, it wouldn't be squishy.

Skip to 2 minutes and 20 secondsSPEAKER 1: [LAUGHS] No, it wouldn't be if it was made out of rock.

Skip to 2 minutes and 23 secondsSPEAKER 2: And it's like soft.

Skip to 2 minutes and 25 secondsSPEAKER 2: And then-- but then it's like hard in the middle.

Skip to 2 minutes and 28 secondsSPEAKER 2: It's also like fluffy on the top, but then it's like hard in the middle.

Skip to 2 minutes and 33 secondsSPEAKER 1: Oh. Can you feel that as well?

Skip to 2 minutes and 34 secondsLINDY: Yeah, I think I know it is.

Skip to 2 minutes and 36 secondsSPEAKER 1: What do you think it is?

Skip to 2 minutes and 39 secondsSPEAKER 1: It's a pom-pom? What makes you think it's a pom-pom?

Skip to 2 minutes and 41 secondsLINDY: Because it's soft and it's got something hard in the middle.

Skip to 2 minutes and 44 secondsSPEAKER 1: And sort of shape is it? Because you've not really described what shape it is yet.

Skip to 2 minutes and 48 secondsSPEAKER 2: I think it's like a sphere.

Skip to 2 minutes and 50 secondsLINDY: I was going to say that.

Skip to 2 minutes and 52 secondsLINDY: But like a hair decoration.

Skip to 2 minutes and 54 secondsEMILY: Or maybe like you stick on like a piece of art.

Skip to 2 minutes and 58 secondsSPEAKER 1: On a piece of art. So why would it be good for a piece of art or a hair decoration?

Skip to 3 minutes and 3 secondsSPEAKER 3: Because it's fluffy and it's light.

Skip to 3 minutes and 10 secondsSPEAKER 3: And it's really easy to hold. It's not that heavy.

Skip to 3 minutes and 15 secondsSPEAKER 3: It feels like something squishy.

Skip to 3 minutes and 19 secondsSPEAKER 3: It feels a bit like Play-Doh.

Skip to 3 minutes and 23 secondsSPEAKER 3: Because it's quite-- if you touch it, it's not squishy enough to be slime. And it's play-- and I think it's Play-Doh because when you're holding it, it's quite hard. If you're just touching it. And then when you actually squish it, it feels better.

Skip to 3 minutes and 47 secondsSPEAKER 1: What makes it good for Play-Doh? What properties?

Skip to 3 minutes and 49 secondsEMILY: Because if it-- because it's squishy and you can mould it better. Because if you had something hard, you wouldn't be able to like mould it. Because it would just be in the shape it was.

Skip to 3 minutes and 59 secondsSPEAKER 1: So it wouldn't change shape.

# Definition of a solid

If children have the misconception that all solids are hard and are unable to be bent and squashed, a good activity to complete is the Explorify activity, Changing Shape. Watch this video as an example of how this misconception is being explored.

This activity asks children to explore lots of different materials that can all be moulded. The discussions that can be explored during this activity will emphasise with children the fact that although solids have particles that are arranged closely together, with force their shape can be altered.

If they believe that all solids are heavy, then when delivering this activity, be sure to include some materials that are light solids such as a sponge or a light plastic.

## Suggest

What solids would you use for discussions based on this activity? Post your suggestions below.

If you wish, take a look at the Explorify activity Changing Shape. The website is free to sign up to.