Goal: Build a rain gauge and measure rain.
You will need: a clear, straight-sided jar, a ruler, tape and a notebook.
Step 1. Tape the ruler to the outside of the jar with zero at the bottom.
Step 2. Put the jar outside in an open spot, away from trees and roofs.
Step 3. Check the jar at the same time every day.
Step 4. Read the water level on the ruler and write it in the notebook.
Step 5. Empty the jar after each reading.
Tip: After a week, add up your readings to find the total rainfall.