Terry Hudson is a caver who has to work in very wet and cold conditions. He explains how he wears a dry layer under his waterproof boiler suit. This works by trapping air next to his body which keeps him warm. He also explains how a wetsuit works. It is made out of tight rubber material and traps a thin layer of water next to his body which keeps him warm.
This clip could be used to start an experiment where the children have to test and find the best materials for insulation. The class could also investigate what properties rubber has which make it good to use in a wetsuit.