Last updated: September 15, 2015
- Grade Level:
- Middle School: Sixth Grade through Eighth Grade
This activity illustrates how the sizes of mineral grains increase with cooling time. Students role play as minerals that have already formed from elements, and now move within a magma chamber. They “search” for like minerals during teacher-designated short, medium, and long “cooling periods.” Students will also examine similarities and differences in samples or photos of an extrusive rock (andesite) and an intrusive rock (granodiorite), two rock types commonly found at Mount Rainier National Park.