Find out how to build a rain gauge.

For this experiment you'll need...

  • a ruler
  • a marker pen
  • sticky tape
  • scissors
  • a plastic bottle

To find out how to make a rain gauge watch the video below or read the instructions underneath the video.


  1. First take your plastic bottle and cut the top off about 10cm from the top.
  2. Then turn it upside down and place it within the lower half of the bottle.
  3. Use sticky tape to secure it around the top.
  4. Now use a ruler and a marker pen to mark on some measurements on the side of your rain gauge.
  5. There we go, now it's complete! Take it outside and leave it somewhere secure or perhaps dig a hole and bury it in the backyard.
  6. Now you just need to wait for it to rain! Once it has rained you'll be able to see how much water has been gathered. Make a note of how much water has been gathered every single day and track the progress throughout the week.

Science behind the experiment

This homemade rain gauge measures the rainfall in your outside space and is a great way to see what your local weather is doing and monitor rainfall patterns. By monitoring these patterns at particular times of the year you can predict what the weather might do in the future. Scientists measure rainfall patterns using a slightly more sophisticated version.

Did you know Thinktank has it’s own weather station in the Science Garden? It measures: air pressure, air temperature, precipitation, humidity, wind speed and more! See the Birmingham Urban Observatory websiteto have a look.

Activities and questions:

Can you compare the weather forecast in your area with the rainwater you collect, how accurate is your local weather forecast?