Imagine this: your lunch got wet in your bag after a rainy walk to school. Or an egg cracked on the way home from the shop. What went wrong?

If the job is keep lunch dry, which property matters most: soft, strong or waterproof? Your group will find out.

Match to the job. A material is what a thing is made from. Matching to the job means choosing a material because its properties fit the job, not because it looks nice.

Saying it from evidence sounds like this: I wanted a bookmark that would not crease. I bent paper, card and plastic twenty times each. The plastic came back flat, so I chose plastic because it bends and keeps its shape.

Notice the order: what I did, what I saw, what I chose and why.

Each group gets one job card: keep a sandwich dry, protect a fragile egg, or make a strong bag handle.

Talk for one minute. What does your job need the material to do? Which materials on the tray do you predict will work best, and why? Be ready to say your prediction aloud.

Your job card shows a first test you can try. Test at least three materials. Notice which properties help and which get in the way.

Sort your tested materials into groups that match your job. Use property labels such as waterproof, soaks water, strong, tears easily, soft and cushioning, or stiff.

Be ready to move one material and explain why its property fits or fails the job.