In this simple and adaptable activity, students will model how the rock cycle transforms rocks by performing different actions on a clay "rock." This creates a way for students to interact with the rock cycle in a tangible way, and to model a process that takes thousands of years in just 1 class period.
The only supplies you need are different colors of clay, baggies, and a heat source. You could get by without a heat source, but a hot plate speeds things up.
I use this activity right after introducing sedimentary, igneous, and metamorphic rocks to my middle school classes, but it could easily be adapted to fit into early elementary classes, all the way up to high school and even college earth science/geology courses.
Also, this is my first submission, so feel free to provide feedback or ask any questions.