Create a homemade rain gauge using simple materials. You'll need: a clear straight-sided container (plastic bottle cut in half, clear cup, or jar—must have straight sides for accurate measurement), a ruler, waterproof marker or tape, and a flat outdoor surface for placement. Cut a large plastic bottle about 2/3 up and invert the top into the bottom to create a funnel (prevents evaporation). Or just use a straight-sided glass. Use the ruler and marker to mark measurement lines on the outside: 1/4 inch, 1/2 inch, 1 inch, etc. Place your rain gauge in an open area away from trees, buildings, or eaves where rain can fall directly into it. Secure it so wind doesn't knock it over (bury slightly, weight with rocks, or use a stand). Explain that meteorologists use rain gauges to measure precipitation and track weather patterns.

Now wait for rain! Each time it rains, go outside afterward and check your rain gauge. Read the water level against your measurement marks: 'We got half an inch of rain!' Record the date, time (morning or afternoon), and amount in a notebook or chart. Empty the gauge after recording (pour water out carefully). Reset for the next rain. Track rainfall for 1-2 weeks or through 3-5 rain events, whichever comes first. Between rains, check daily to make sure the gauge is still in place and empty (no rain means zero inches—that's data too!). Discuss what you notice: 'This storm only gave us a quarter inch, but yesterday's storm gave us two inches. What was different?'

Use your rain collection as a springboard to teach about the water cycle. Explain: water evaporates from oceans, lakes, and rivers (heat from the sun turns liquid water into water vapor gas). Vapor rises and cools, forming clouds (condensation—gas turning back into liquid droplets). When droplets get heavy enough, they fall as rain, snow, or hail (precipitation). Rain soaks into the ground or runs into streams and rivers, eventually flowing back to oceans. Then the cycle repeats forever. Draw a diagram together: sun, ocean, evaporation arrows, clouds, rain, rivers, back to ocean. Discuss that the rain you collected was once ocean water, then cloud droplets, now liquid in your gauge. Connect to daily life: the water you drink has been cycling through Earth for billions of years!

Review all your rainfall measurements together. Calculate totals: 'We collected 3 inches of rain over two weeks.' Find the average: 'Five rainstorms averaging 0.6 inches each.' Compare events: 'The biggest storm gave us 1.5 inches, the smallest only 0.1 inches—that's a huge difference!' Discuss what the data tells you: Was it a wet period or dry? How does your total compare to normal rainfall for your region (look up average precipitation online)? Graph the data if your child is old enough. Predict future rainfall: 'If this pattern continues, how much rain might we get next week?' This teaches data analysis, a core scientific skill. Celebrate that your child just did real science: collected data, recorded it systematically, and drew conclusions.

Discuss what you learned about rainfall and water. Talk about water scarcity: some places get very little rain and face droughts, while others get so much they flood. Your rain gauge shows how much (or how little) water falls naturally. Connect to conservation: 'Now that you see how rain provides our water, does it make you think differently about wasting water?' Discuss ways to conserve: shorter showers, turning off taps, fixing leaks, using rain barrels to collect water for gardens. Celebrate that your child understands the water cycle and can measure precipitation. Decide if you want to keep tracking rainfall long-term or move on. Either way, you've learned valuable science skills: observation, measurement, data collection, and analysis.