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If there is one thing you can rely on in England during winter, it is the unpredictability of the weather. The forecasters tell us it will be a mild winter – we get snow, last year we were told we would get 100 days of snow! Well, I am still waiting for that to happen. This year I decided that rather than waiting for the weather to make up its mind about if it will snow or not, we should just make our own snow – well snow crystals.

This week my charges had a friend over, and he happens to love mixing potions together, so this was the perfect experiment to do with them all before tea. As a word of caution: this activity, although quick to set up and do, will take about a week to see through.

To make your own snow crystals you will need:

  • 2 jars
  • Wool
  • 2 paper clips
  • Hot water
  • Bicarbonate of soda
  • Spoon
  • Plate
  1. Pour some hot water into your jars.
  2. Mix in the bicarbonate of soda, you want to saturate the water with this so keep adding it until no more will dissolve, and you are left with a layer of it at the bottom.

    Mixing the solution together

    Mixing the solution together

  3. Cut a length of wool that will go between the two jars (with a plate between them).  At either end of the wool tie a paperclip, this will help keep it in the jars and the water.  Put either end in one of the jars.
  4. Now leave it for a few days or a week and keep checking back to see if any of your crystals are forming.
    Leaving the snow to grow

    Leaving the snow to grow

    After a few days

    After a few days

    After a week

    After a week

    Playing with our snow

    Playing with our snow

The science behind it:

The water and bicarb solution will travel up and along the wool, as the water evaporates it will leave behind the crystals of bicarb.  If you are lucky you may get both stalactites and stalagmites growing.

This activity may help the development of:

  • Scientific inquiry – this is a great experiment to introduce little ones to the concept of dissolving, saturation and evaporation.
  • Vocabulary
  • Expressing opinions about what will happen and why it is happening.

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