Make a Fossil!

Use shells, plants, or other small objects to make prints in a special clay made with coffee grounds.

What You Need:

  • 1 cup coffee grounds
  • 1 cup flour
  • 1/2 cup salt
  • 1/2 cup cold coffee
  • Mixing bowl
  • Mixing spoon or spatula
  • Wax paper
  • Cookie cutter or glass to make circles
  • Shells, ferns, or small animal and insect toys

What You Do:

  1. Mix the dry ingredients together, then stir in the coffee to make a dough.
  2. Press the dough onto the wax paper with your hands or a spatula.
  3. Cut circles out of the dough using the cookie cutter or upside-down glass.
  4. Press the objects into the dough, then carefully lift them out.
  5. Let the dough “fossils” harden overnight. If they are not completely dry, turn them over and let them dry for another day.

What Happened:

In this project, you made your own fossil by using clay, and pressing objects into it to make a print. When the clay hardened, the print still showed up. Sometimes footprints left by animals and prints of plants turn into fossils. When they do, the prints are pressed into rock, just like the prints you made in this project. When fossils of hard objects like bones and teeth are formed, they usually form a raised-up “rock” in the shape of the object instead of an indentation. That’s because the objects get buried and their shape is filled in with different minerals from the ground they are buried in.

What Would A Dinosaur Eat?

Dinosaurs like sauropods (examples: Apatosaurus and Brachiosaurus), stegosaurs (examples: Stegosaurus and Kentrosaurus) and ceratopsians (examples: Triceratops and Styracosaurus) were herbivores, which means they only ate plants. They would probably eat just about every part of plants like leaves, stems, roots, blades of grass, and even twigs and branches. Dinosaurs who were herbivores had to eat a lot more than those who were carnivores (meat-eaters) to get full, since plants are not as filling at meat. They had blunt or flat teeth to help them pull leaves off of plants and grind up the plants. Some herbivore dinosaurs had pouches in their cheeks where they could store food before swallowing it and some would swallow rocks which helped them grind up the plants they ate.

Get permission to go outside and hunt around your yard or a park for things that herbivore dinosaurs might have liked to eat. Think about what kinds of plants different dinosaurs might have liked or been able to find. For example, dinosaurs with long necks like Apatosaurus could reach way up in trees while smaller ones with short necks and large heads like Polacanthus probably liked to eat shrubs and plants that grew lower to the ground.

How many plants do you think a dinosaur could eat? It’s hard to know exactly, but we can get an idea of how much they might have needed by studying other large herbivores that are still alive today, like giraffes. An adult male giraffe can eat up to 100 pounds of plants in a day! Most plant-eating dinosaurs were much larger than giraffes, so they needed even more plants to eat.

What do you think the places where dinosaurs lived looked like compared to what your yard or the park you visited looked like? Do you think there would be more plants? What else do you think the land needed for the dinosaurs to live?

Go here for Science Lessons and ideas for teaching kids about dinosaurs and fossils.