Summer science: A storm in a jar

June 28, 2018

Keeping the class quiet just before the summer holidays is no easy feat. With sunny weather, barbecues and six weeks off on the horizon, it’s tricky to keep even the most committed pupil (and teacher) focused.

With the summer comes long evenings and humid, sticky days and unpredictable weather. One of the most exciting parts of the season is the possibility of a summer storm.

With rumbles of thunder and white cracks of lightning across the sky during the golden hours of the evening, storms are a sensory overload and incredible to witness (as long as you’re inside… safety first and all that).

What better time to teach the class about extreme weather, starting with thunderstorms?

Storm in a jar

The lesson:

Thunderstorms are produced by a cumulonimbus cloud, which then creates gusts of wind, heavy rain and hail. These are caused by moisture, warm and unstable air, and lift, most commonly occurring on summer evenings.

With 16million global thunderstorms every year, meteorologists estimate that at any given moment, there are 2,000 thunderstorms in progress. With every thunderstorm producing lightning, this makes them incredibly dangerous.

Containing 20,000 or more amperes of current, a lightning strike spreads out in the ground, making the area potentially deadly for those who come within its contact.

The experiment:

The storm in a jar will show pupils what happens when clouds become overly saturated and heavy, producing heavy rain storms.

What you’ll need:

  • A large glass jar (or several, if you’re splitting the class into groups)
  • Water
  • Shaving cream
  • Food colouring (or glow in the dark paint, if you want to create something a bit more magical- just remember to turn off the lights)
  • Eye droppers

How to do it:

  • Fill your jar just over ¾ of the way with water
  • Using the shaving cream, create your ‘cloud’ on the top of the water
  • Taking eye droppers, add the food colouring to the shaving cream until it is saturated and heavy enough to start raining colour into jar
  • Keep adding colours and see what happens!

Trying this out before the end of term? Share your pictures with us at @TechniTeach.


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  •   What is Techniquest?

    Techniquest is an educational charity, with a science centre in Cardiff Bay. Our mission is to embed science in Welsh culture through interactive engagement. We provide a range of services to schools and teachers to complement formal education provision in Wales and work extensively with public audiences.

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