Here's a terrific video from Geology Kitchen on three types of rocks and how they form. (Yes, that's a kitchen, and the host is wearing a "Kiss the Geologist" apron.) The examples he uses can be replicated in the classroom.
"...the evolution of the Earth's surface in reverse, from the present day to, at the very bottom, 600 million years ago, when nearly all of the planet's landmasses were joined together in the Antarctic. The first sequence shows roughly 90 million years of backward evolution, the continents pulling apart from one another and beginning a slow drift south. They were mapped using the Mollweide projection, and, in all cases, are by Ron Blakey."