Layers of the Earth Project

What You Need:

• 2 cups flour
• 1 cup coarse sea salt
• 4 teaspoons cream of tartar
• 2 tablespoons vegetable oil
• 2 cups water
• Cooking pot
• Spoon
• Cutting board
• Food coloring

What You Do:

1. Have your child put the flour, salt, cream of tartar, vegetable oil and water into the pot.
2. Heat on low, stirring constantly.  The dough will start to come together and become very thick.                           
3. When the dough pulls away from the sides of the pot, remove it from pot and knead for 1-2 minutes.  You will notice that there are still crystals of salt.  Remind your young learner that the earth is made up of a wide variety of minerals. These salt crystals are a visual reminder of that fact.
4. Help your child separate the dough into 6 balls of increasing size, starting with a ball about 1 inch in diameter. 
5. Your child should now use the food coloring to dye the balls one at a time, starting with the smallest ball.  This one is red.  Add 6 drops of food coloring.  Fold into the dough with a spoon until the coloring has blended in partially and then use your hands.
6. The next largest ball is going to be orange.  Add 4 drops of yellow food coloring and 2 drops of red.  Repeat the mixing process.  The proportions of food coloring for the other balls of dough, smallest to largest, are as follows: yellow/7 drops yellow coloring; green/7 drops green coloring; grayish green/7 drops of red food coloring, 2 of green, 3 of blue, and 3 of yellow coloring; blue/7 drops of blue.  Add and mix as directed in step 5.
7. Now your child will form a cut away model of the Earth.  First, he will make the inner core.  Working with the red ball of dough, he should press it onto the cutting board, until it is flattened on one side.
8. Next he will add the outer core, the orange dough.  He should flatten this dough into a pancake and drape it over the red dough, pressing it close without smashing the half ball flat.
9. Next comes the mantle, the yellow dough.  Again, he should made a pancake and add this to the outside of the half ball. 
10. Repeat this process with the crust (the grayish green dough) and the water (the blue dough). 
11. Last but not least, he should use the green clay to form land masses and press them onto the half globe.
12. Viewed from the top, he can see the Earth – land and water.  But if he carefully picks up his model and turns it over, he will see a cutaway model of the Earth – red inner core, orange outer core, yellow mantle, greyish crust, blue water and green land.