| Category | Activities |
| Time to allocate (mins) | 25 |
| Outcome | Plaster of paris mould |
| Resources | PLASTER OF PARIS LITTLE PLASTIC CREATURES OR OBJECTS – These objects should be small enough to fit in the middle of the cup. We trimmed a few small plastic toys to make them fit. Small shells and found objects with interesting shapes work well. You can usually find tiny creatures at “dollar” stores. WATER and a container for pouring, e.g., a large container with a small pour spout or a large water bottle (or several bottles) with a spout that allows you to pour in small, controlled amounts, for example, approximately 2-3 tablespoons at a time. MODELING OR POTTERY CLAY – Play-dough doesn’t perform well because it swells, distorting the impression. Modeling or pottery clay is best and can be reused again and again. SMALL PAPER CUPS – each child receives one empty cup and then another cup later, half-filled with dry plaster. POPSICLE STICKS or stirring sticks. One for each child. PERMANENT MARKER – only necessary for large groups. (Used to label.) |
| Instructions | 1. The flattened clay ball should take up less than half the cup. 2.Flatten the clay well before making the impression. 3.Place the object upside down in the clay. 4.DO NOT bury the object. Share with your friends. If there is a large group, one set can be passed around, reducing cost. 5.If a fish, insect or reptile is too big for the small paper cup, consider trimming it. Add pieces to other objects to morph them into weird creatures. 6.Using one of the paper cups to measure, gently add ½ cup of plaster on top of the impression. 7.Add 2-3 tablespoons of water. The consistency should be like thick pancake batter. 8.If too much water, add small amount of plaster QUICKLY! 9.Stir the water and plaster together gently, making sure not to poke the impression below. 10.Let it sit for a minimum of one hour or overnight (recommended). 11.Tear open the cup over a trash can to reveal your amazing fossil. 12.Reuse the ball of clay for another project. Keep in an airtight container. 13.Compost the paper cup. 14.Use larger cups/containers to make bigger fossils. Remember, you will need more plaster and clay. |