I have done bicarbonate of soda 'volcanoes' in the past, but have found it to be quite a short-lived activity for my 2.5 and 3.5 year olds.
Today I had the idea of doing something with the bicarbonate of soda and vinegar that would engage them for a little longer.
I got out our sensory trays (aka plastic cat litter trays from a one pound discount shop!) and sprinkled the bottom with a fine layer of bicarbonate of soda. I then mixed a couple of bowls with a mixture of vinegar and paste food colouring to make a vinegar 'paint'.
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| They noticed the fizzing straight away |
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| Doing a bit of stirring |
Without prompting my 3.5 year old declared "it smells of science!" - this is because when we have played with vinegar volcanoes in the past I have described it as science, so this goes to show that sensory stimulation causes incredible cognitive development in toddlers.
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| "Its making circle patterns, Mummy!" |
Watching the girls play with this set up was fascinating. I hadn't considered that the spoons being used again to scoop up more liquid would leave small amounts of bicarbonate of soda behind in the bowls. My 2.5 year old said "my red water is making a noise!" - she was referring to the big bubbles she was popping with her spoon that were creating a fizz.
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| Small amounts of bicarbonate of soda created big bubbles in the red vinegar mix |
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| "I've got fizzy monster hands!" |
As far as messy activities go, this one is a pretty simple clean up, providing you cover your main surface with an easy wipe cloth. Dunking their hands in the warm soapy washing up bowl to help me wash the containers afterwards was another sensory bonus!
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| Helping to clear the activity away |












