10 Easy Science Experiments for a Rainy Day

If you’re looking for easy activities to keep kids busy on a rainy day, you’re in the right place. Make the most of the weather with my collection of easy science experiments for a rainy day.

Children can use the rain as part of a science experiment or be inspired by rain and weather.

I hope these rainy day activities cheer up a gloomy day wherever you are!

Science Experiments for a Rainy Day

1. Make a simple rain gauge

A rain gauge can be made easily from a plastic bottle. Either place a plastic ruler inside to measure the amount of water or use a permanent pen to mark measurements on the side.

Remember to empty the rain gauge daily to get a new measurement the next day.

Image of a rain gauge made from a plastic bottle

2. Waterproof a Welly Boot

Find out about waterproof materials with my waterproof a welly boot STEM challenge.

The activity sheet is free to download, and then all you need are materials to test, sellotape and water.

3. Make a rain cloud in a jar

Discover how clouds form and why rain falls with a colourful rain cloud in a jar demonstration.

Clouds look grey when they are so full of water droplets that light cannot travel through them! This is why grey clouds are a sign that rain is about to fall.

4. Make a rainbow indoors

Make a rainbow indoors using a prism and torch. Rainbows are seen in the sky opposite the sun and are caused by the refraction ( bending of light ) and dispersion ( splitting up ) of sunlight in drops of rain or mist.

If you don’t have a prism, look for a rainbow in bubbles!

prism on a window sill splitting light into it's constituent colours

5. Make a water cycle model

A water cycle model is a great way to learn about evaporation and precipitation!

The model allows children to see condensation build up on the cling film, which falls as precipitation. You’ll need to wait for a sunny day to get this to work, but a rainy day is a great time to plan the activity.

Water Cycle Experiment, using a bowl, cling film and water

6. Tornado in a Jar

Tornadoes are powerful vertical columns of rapidly spinning air that can cause vast amounts of damage. A tornado in a jar is a great way to visualise this exciting weather phenomenon.

Image of a tornado in a jar with a background of a real tornado

7. Make lightning with a balloon

Did you know you can create a tiny spark of static electricity with a balloon and a metal spoon?

You’ll need to be in a dark room to see the spark.

8. Create a thunderstorm

A thunderstorm is a storm with thunder, lightning and often strong wind and rain. Lightning is a giant spark of electricity between a cloud and the ground, inside or between clouds. Thunder is the sound created by the rapid heating of the air around a lightning bolt. The air expands very quickly, creating a loud boom noise.

Thunderstorms form when warm, moist air rapidly moves upwards. The air cools, forming clouds that produce lightning, thunder, and heavy rain.

A candle carousel is a fun way to demonstrate how hot air rises.