Pardon this plug.

I hope you don't mind if I do a little advertising. I developed three products (listed below) for WARD'S Natural Science Establishment. I receive a royalty payment based on the sales of these, so naturally I hope you will consider them as you are planning your future purchases. They are all designed for use with 7-10th graders.

1. Exploring Convection: includes two of my best labs . . . one to help students understand ocean currents and the other to help them understand the development of winds (see "Hot Link" below)

2. From Lines to Landforms Kit: students build before and after models of Mt. St. Helens and Crown Butte ( a Montana laccolith): includes display materials

3. What Happened at Lake Nyos Kit: helps students understand that gases also have density differences, and introduces them to the concept of dissolved gases.