STEM Activity: Make Your Own Fossils

I was looking for a fun activity that could incorporate a short hike and a quick and fun STEM activity. I came across this cool looking fossil print activity at the STEM Mom blog. I liked it because it was a simple and inexpensive play dough style recipe made with coffee grounds and made the play dough look like rocks.

Here is her recipe:


Mix together 

  • 1 cup flour
  • 1/2 cup salt
  • 1 cup used coffee grounds
  • 1/2 cup cold, leftover coffee
Mix all ingredients together, and knead extra flour into the mixture to give it a doughy texture. Press into pans and make fossil imprints. Can let air dry, or bake in an oven on 200 for 20-30 minutes. “
On our hike, the kids all picked up items from nature that they wanted to make a fossil out of. The above recipe makes a very realistic looking fossils.
These were super fun! If you want to take this a step further, the original lesson has some additional activities and free handouts you can use for enrichment.