Materials

• 2 liter soft drink bottles
• Small rocks
• Gravel
• Dirt
• Guppy
• Water Plants
• Grass seed
• Sand
• Cheese Cloth
• Water
• Snail (optional)

Directions

• Cut the two bottles in half.
• Discard one bottle bottom.
• Layer one bottom with rocks
• Fill that bottle one half full of water.
• Add water plants, guppy and snail to the water.
• Tie cheese cloth around the lip of one bottle top.
• Invert that bottle into the bottom half of the watter filled bottom.
• Layer this portion of the bottle with rocks.
• Add about a half inch of sand.
• The add about 2 inches of dirts.
• Plant the grass seeds and water.
• Put the other bottle top on top of the inverted bottle top.
• Tape the three bottle together with clear tape.
• Set the bottles near a window and watch the life cycle.
• Record results daily.

Idea courtesy of Jaimie McGill.