Education 325 (Earth Science) Starburst Rock Cycle for Kids: Easy, Fun and Yummy! Could easily make sedimentary rocks (with pressure and Starburst) in the classroom. The other types of rocks would be harder as you need heat.
science Rock Cycle - When picking rocks for hardscapes use Metamorphic rock, especially with water (so it doesn't leach anything into water) also important to know what type of rockscape animals may have evolved in.
Education 325 (Earth Science) Volcano Lava Activity - free hands-on science activity for or grade elementary kids. Part of a complete unit on Rocks: Rock Cycle, Erosion, & Natural Hazards. Meets Common Core and NGSS.