 You can help a child learn about rainfall by using a jar or glass to measure it. Place the jar outside. After it rains, the child can put a stick next to the jar and mark the water height. Then they can empty the jar and leave it outside. After it rains again, you can ask, do you think it rained more or less than last time? After they guess, they can check the jar and compare it with the mark from last time. This activity helps the child learn about observing and measuring.