Soil Horizons

Time: About 45 minutes

Big Idea: Explore the value of soil and develop their understanding of soil particle size. Then have some fun with making an edible dirt pudding.

 What You’ll Need:

• Real Soil Jar
  • Mason Jar
  • Dirt from outside
  • Water
  • Spoon
• Edible Soil Cup
  • Clear Plastic Cup
  • Chocolate Pudding (1-2 Chocolate Pudding Cups)
  • Oreos
  • Gummy Worms
  • Graham Crackers
  • Chocolate Chips/ Cereal
  • Whipped Cream

Part 1: Real Soil Jar

1. Fill the mason jar 1/3 full with soil from outside. Add water to fill up the jar while leaving a small gap for air.
2. Shake the soil and water until mixed well. About 3 minutes.
3. Set the jar aside and let settle for 20-30 minutes (while soil particles separate by layer). To save time, start making the edible dirt pudding cup now.
   1. After the soil has been separated, identify the soil particles by size (sand, silt, clay). Sand is at the bottom of the cup (largest), silt is in the middle, and clay is at the top (smallest soil particle).
   2. Talk about how these soil particles have formed layers similar to horizons.
   3. Why do you think soil is important?
   4. How does soil particles change the movement of water?

Part 2: Edible Dirt Pudding Cup

1. Layer the “soil” in the cup by adding the materials in soil order.
   1. “Rocks”: Chocolate Chips or Cereal
   2. “Subsoil”: Crushed graham crackers
   3. “Soil Structure”: Chocolate Pudding
   4. “Topsoil”: Crushed Cookies
   5. “Decomposers”: Gummy Worms
   6. “Humus”: Whipped Cream
2. Eat the dirt pudding and discuss the idea of soil layers with the child.
   1. What was your favorite layer?
   2. What do you think is developed first, the bottom or top layers?
   3. Why are decomposers important for soil health?