These down feathers are able to trap a lot of air and keep the birds warm. Ask the children if they would like to do an activity that will help them to find out if air can actually keep you warm. Place your container of ice water on a low desk, so that a child can easily reach into it. Because it is very difficult to seal bubble wrap against all leaks, put a plastic bread bag over the bubble wrap and also place a plastic bread bag over the child s other hand. Now the child should place both hands into the ice water.
Some children try to leave their hands in the water for an especially long time.
Do not let them keep the unprotected hand in the ice water for longer than 30 seconds. Double-paned windows work on the basis of this principle and use the air space between the two windowpanes as an insulator. Feathers, especially down feathers, trap a lot of air because of their intricate, fluffy shape. It is the air that keeps the birds from feeling the extreme cold temperatures.