Plate tectonics video-you could create something similar or BETTER using Explain Everything.
Make an aquifer-look for plans on the internet or ask Mr. B for some suggestions
Create some weather instruments.
Make a rock-mix some dry sand, small gravel, bits of rock in a cup. Mix up a super solution of Borax and slowly cover the dry mixture with it. Do not add so much Borax solution that there is liquid covering the top of the sand mixture.
Button solar system
Erosion and Weathering