How to Make a Layers of Soil Model Using Plaster of Paris

Pour your plaster of Paris into your bowl.

Add water slowly, stirring with your long-handled spoon. You want your plaster to be creamy, but not too thin. Add water slowly till you achieve the desired consistency.

Set your tins onto a flat surface and pour the plaster of Paris into the tins. Split the mixture between the two.

Grab one of the tins by its side and lift gently. Tap the bottom of the tin on the flat surface. This will help to remove any air bubbles. Repeat with the second tin. Allow the tins to sit overnight for the plaster to dry.

Remove the plaster of Paris from the tins. It should pop out. If it does not, simply pull the tin away from the hardened square.

Apply super glue to the underside of one of the blocks of hardened plaster of Paris.

Set it atop the second block.

Lay the stacked blocks onto a flat surface and place a heavy book on top of them. Let stand for an hour.

Mark five separate sections on your blocks using your pencil. Trace the marks around your entire block. These sections will represent the soil levels. The top level should be the thinnest. Refer to your picture of soil levels to determine how large you want to make each section.

Paint your sections. The top section should be green, representing grass. The second should be dark brown to represent topsoil. The third will be light brown or clay colored to represent subsoil. The fourth should be gray to represent parent material soil and the fifth will be black to represent bedrock.