Today's forecast: wet, wet, wet

5th March 2010 at 00:00
A lesson on the water cycle from the Science Festival's travelling arm goes down a storm with pupils at a Glasgow primary

Big, fat, wet lumps of snow have been falling in Glasgow all day.

It isn't lying in the city, but the headteacher of Copeland Primary, Sandy MacArthur, has been receiving regular updates from his wife about the situation in his neighbourhood, where it is 13cm deep and counting.

With the weather putting on such a riveting performance, it could hardly be a better time for the travelling arm of the Edinburgh International Science Festival, Generation Science, to put on its new show, a meteorological adventure that touches on how snow is formed.

The Wonderful World of Water takes pupils on an intrepid journey through the water cycle. The show, which is aimed at P4-7, was conceived following feedback from teachers stating the water cycle was a difficult section of the curriculum to teach.

Joan Davidson, general manager of Generation Science, says: "Following feedback from schools and teachers at the end of our 2009 tour, we have developed our programme and revised our shows to ensure that our teaching continues to be relevant and to assist teachers in explaining complex science subjects in simple and fun ways."

The children's guides on their journey are Wilma Winds and Wendy Waters, weather reporters who broadcast live from Copeland.

In the past 24 hours, 10cm of rain has fallen in the playground - the highest rainfall in the past 50 years, reports Wilma. And it's set to get worse, with fog and snow on the way, she adds.

"Where is all this wet weather coming from?" she asks, when the bulletin is over. With these words, the children's quest to uncover the secrets of wet and wild weather begins - what are clouds? How are they formed? If they are made of water, how does it get up into the sky?

Using a hot plate, Wendy, the brains of the operation, shows that when water is heated it evaporates and turns into a gas - water vapour.

"It's disappeared!" exclaims Wilma, staring in disbelief at the hot plate. "Where is it going?

"Check your pockets," she suggests to one boy, giving him a gentle nudge.

But nobody boils the seas and the lakes, so how does the water evaporate to form clouds, Wilma asks.

A tub of water left on a window sill for two weeks will begin to evaporate even if it's just left to its own devices, explains Wendy. And when pupils' hands are sprayed with a fine film of water, it too quickly disappears. Heat gives the particles energy, says Wendy.

"The more energy they get, the faster they move, until they break free of their bonds and change into a gas."

When the particles cool down they change back into a liquid, Wendy continues. To prove the point she places a can of iced water on a desk. It quickly develops a layer of condensation on the outside.

"When the water vapour bumps into the cold surface, it cools and turns back into a liquid," she says.

Clouds are formed high in the sky where it is much cooler. Snow comes about when temperatures are very low: zero or below.

"Clouds are made up of lots of little ice crystals," says Wendy. "When they grow too heavy, they fall as snow."

Casey Sweeney, in P5, thought that clouds were made of fluff before the show. But now she knows they are "just gas" and the same water goes "round and round".

James Henry, in P4, took part in one of the competitions during the show. Four pupils were challenged to see how quickly they could dry Wilma's damp socks. James decided to shake his dry and did so with gusto, but the pupil who used the hairdryer triumphed. Nonetheless James is an enthusiastic advocate of the Wonderful World of Water.

"It was brilliant," he says. "I never knew about clouds or the water stuff, but I knew about snow."

It was fun and exciting and very, very funny, says Erin Prentice in P7. "I'm sure everybody enjoyed it," she concludes.

Generation Science's spring touring dates are January 25 to March 26 and during the summer term from April 26 to May 28 The 22nd Edinburgh International Science Festival will take place in Edinburgh from April 3-17


Last year Generation Science, the Edinburgh International Science Festival's schools touring programme, visited more than 600 primary schools and reached more than 60,000 pupils in 31 local authorities, from Stranraer to Shetland.

This year, for the first time, it will be taking Ella's Wobble to nursery schools. Ella's Wobble is an interactive show in which pupils build their own instruments and discover how sound is made, how pitch changes and where echoes come from. It follows the adventures of Ella, who loses the sound of her voice and sets out on a journey to find it.

Deep Sea World's new show Underwater Explorers allows pupils to handle live coastal creatures and teaches them about the effects that pollution can have on our environment and how to protect marine life. It is aimed at P1 to P7.

Log-in as an existing print or digital subscriber

Forgotten your subscriber ID?


To access this content and the full TES archive, subscribe now.

View subscriber offers


Get TES online and delivered to your door – for less than the price of a coffee

Save 33% off the cover price with this great subscription offer. Every copy delivered to your door by first-class post, plus full access to TES online and the TES app for just £1.90 per week.
Subscribers also enjoy a range of fantastic offers and benefits worth over £270:

  • Discounts off TES Institute courses
  • Access over 200,000 articles in the TES online archive
  • Free Tastecard membership worth £79.99
  • Discounts with Zipcar,, Virgin Wines and other partners
Order your low-cost subscription today