We have been studying soil and rocks for a few weeks. To end our unit, each 3rd grader made their own plaster of paris fossil. We recycled empty (and cleaned!) milk cartons to create these fossils. After cutting down the carton, piece of modeling clay is pressed down into the bottom. Be sure to fill all the corners of the carton! Then, the students use shells to make impressions on the modeling clay. The plaster of paris is then poured over the clay. Let it set up and then tear away the carton & peel off the clay. Each student will have their own fossil to keep!