Overview: It's bedtime and Maddie is finding out about different things we sleep on and in! At a campsite she uses a special thermal camera to show how the layers in a sleeping bag work by trapping warm air inside to keep us warm. Next, Maddie visits a mattress factory to see how a mattress is made from layers of foam and material, a bit like a giant sandwich! She uses a special camera to see the tiny holes in the sponge that make the mattress nice and soft for us to lie on.