Add 2 or 3 drops of red dye to the water. Holding perforated cup over the model, pour the tinted water into the cup to simulate rain. Pour until the water collects up to or into the gravel. Mark the water level all around the glass with the grease pencil. This line represents the water table.
Groups compare and describe water distribution in their materials.
Add equal volume of tinted water to all 3 glasses, one at a time, using the perforated cup. Time the rate of absorption for each, and record these. With grease pencil, mark the water table level around each glass. Record the lowest level. Compare results among groups.