Investigating the Smallest Size Rock: Clay!

2nd graders are finishing up their unit on Pebbles, Sand and Silt by investigating the smallest size rock...clay.  It is so small, that you can't isolate one grain.  We described how it felt, looked and even smelled. 

We then made two balls of clay and put the larger ball into a paper cup and the smaller ball into a vial filled with water.  We made predications about what the clay would look like the next science class.

It was not a surprise to most of the 2nd graders, that the following week, the clay in the paper cup was hard. Hard as a rock! They were surprised that even though the clay was hard, it still could break!  We put a little water into the cup to see what would happen....the clay softened up again.

The clay in the water broke apart and settled in the bottom of the vial.  The water changed from milky looking to clear!

It's always fun to play with clay no matter how gooey it is!