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Snow business

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Snow business

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Down in the South of the UK where Snapshot Science hails from, the snow has long since melted and is it now practically tropical compared to the chilly North.

Assuming you are not sick to death of the very mention of the s-word, here are some snowy ideas for fun science lessons for the end of term which you could use (if school is open of course).

Chemistry

The new GCSE specifications cover the use of novel polymers.  Hydrogels are polymers that can absorb many times their own mass in water.  Commons uses are in nappies and soil (where there are used to cut down the need for watering) but a much more interesting use is fake snow.  This can be bought in most department stores around Christmas time or online at all times of year.

For a lesson on hydrogels you could start off by engaging the class by performing a trick.  In secret remove some of the hydrogel from a nappy or use some from another source (this hydrogel is sodium polyacrylate) and place in the bottom of an opaque plastic cup or bottle.  Then show the class the ‘empty’ cup and add water.  After a few minutes, ask for a volunteer to come to the front of the class and proceed to tip the contents over their head.  Hopefully nothing will come out but please practice so you add just the right amount of water!

You could then go onto to show them the instant snow and carry out some of the excellent activities in this ‘Young Engineers’ PDF.  It also contains a useful worksheet outlining how hydrogels work in terms of their molecular structure.

Physics

This idea would be great for KS2 or 3 students.  It is based on the classic concept cartoon which asks students to think about what would happen to a snowman if you put a coat on it.

After showing them the cartoon (see weblink) and getting their first thoughts they can plan and carry out an experiment to find out the answer.  I would supply them with lots of equipment that they could use (crushed ice, beakers, cloth, thermometers, balances) and make it open-ended.

They can work in groups and then design a PowerPoint slide to be shown after the concept cartoon which shows which child was right and what evidence they have to prove this.  They can then go onto to discuss the science behind it as well.

Weblinks and other ideas

Snowman concept cartoon

Why does salt melt ice?  Explained using dynamic equilibrium and a nice interactive animation.  Good context for this when teaching the topic to KS4/5 students.

Outline of a study submitted to the New Zealand Medical Journal which stated that wearing your socks over your boots stopped you from slipping on icy pavements.  Students could discuss possible reasons why (is it increased friction or something else?)

Nice experiment here from the Naked scientists who ask ‘can we use salt water to melt the ice on the roads?’