Students last week, started by observing a diaper and commented on its ability to hold the water that was added. They discussed the idea of water absorption and dissected the diaper to determine what material is responsible for this special property. Students removed the tiny white crystals inside the diaper and tested their ability to absorb by adding water. They were able to see the rapid expansion of the crystals and were encouraged to feel them to note the change in texture.
Students then looked at an application of these water absorbing crystals filling a small round mold with the crystals and soaked them in water. The crystals interlock as they expand, and they maintain the round shape to produce a bouncing ball.