Making Plaster Casts

You can make copies of nature's treasures by using techniques called molding and casting. Follow along and see.

Start by collecting objects that interest you from the outdoors, like twigs, shells, nuts, berries, flowers, and pine cones.

Take a ball of modeling clay or Playdough and roll it out on a flat surface. If the object you want to cast is thick, like a pinecone, then leave the clay thick.

Next, take your object and press it firmly into the clay. But, be careful not to mark the clay with your fingers, and don't press the object in too deeply! You still have to get it out of there before you can make your cast. Gently remove your object so that it leaves an imprint in the clay. You can use toothpicks if you need to, to gently loosen it from the clay.

Then, bend a strip of cardboard into a ring that will fit around the clay imprint, and secure it with tape. Press the bottom edges of the cardboard into the clay, forming a wall around it.

Once that's ready, you make the Plaster of Paris according to package instructions -- about 2 cups of water for 3 cups Plaster of Paris powder. Add the water a little at a time while you stir slowly so you don't get lumps. Now spoon the mixture into the mold so it makes a thick cover over the imprint. You need to work quickly, before the plaster starts to set.

Once the plaster is set, remove the tape from the cardboard ring and carefully peel the cardboard away from the plaster cast. When it's completely dry, pull away the clay. You can wash the cast carefully, and you can even paint it if you want to. Cool, huh?

Sometimes nature has already left imprints for us, like animal tracks. You can make casts of those, too, using the same steps but without the clay -- put a wall around the imprint with cardboard, pour in the plaster, and you'll have a cast of an animal's footprint. Have fun!