My daughter is learning earth science this year. She struggled a bit to figure out plate tectonics so I spent some time finding material on the Internets Tubes to help her out. First, I found some cool YouTube videos. Here's one.
Next I found some nice Google Earth overlays showing the Earth's plates and showing volcanic eruptions in the last 10,000 years.
It made a big difference in her understanding of the subject. Yay!