Kids get in trouble for “bird walking,” which means to start thinking about other stuff instead of the teacher’s topic. As a kid, I was very guilty of this. But, I was bad about doing it when I taught and have a hard time with this as a writer. For example, I was studying about displacement of air in the soil by rainwater this morning to answer a kid’s question.
Why does the ground have bubbles after a rain?
I was designing an experiment about the displacement of air in the soil by water when my brain “switched track” to a funny event at church.
Every pew was filled, but one of the elderly ushers continued to encourage people to move closer so he could seat more people. It was the perfect example of displacement–one person was seated on one end of the pew as the person on the other end was pushed off. An usher for that aisle reseated the person on another pew.
Yep! One person displaced–took the place of–another person. Hey!! That is a great example of the displacement of air in the soil by rainwater. As the rainwater soaks into the soil it pushes the air out and takes its place.
For an activity about displacement, see DISPLACEMENT: AIR WITH WATER