We sent home a small amount of clear hydrogel balls with the instruction to use a liquid to make them grow. Any liquid could be used - the more imaginative the better - and we would see what happened!
The smallest hydrogel balls only take a couple of days to grow so it is easy to take a series of photographs to show this happening.
Here is a set of pictures we took last year.
This week we were able to look at the results of the class homework.
We were very impressed with how many families joined in and how many different liquids were tried.
Some used water and got great results with the balls growing to full size - about 8mm diam - one or two added food colouring to their water - the clear balls took up the colour but in neat food colouring they didn't grow very big. In dilute food colouring they grew well.
Many had used drinks - coke, fanta, lemonade, Vimto - and got quite big balls and some had taken up the colour of the drink.
A couple has used cider vinegar which gave a gold colour but only medium growth.
Milk went off and was very smelly - not recommended!
Cocoa - very imaginative - was a bit smelly too.
We were very impressed with one young man who tried different strengths of food colouring and decided to display his results in clean water so we could all see. The balls in dilute blue grew best and gace a pale shadow of colour but neat colours didn't really grow at all.
We all decided that the balls grew best in pure water. Year 4 thought this could be because drinks have so many other ingredients in them that they stop the balls growing fully.
One total surprise - someone used washing up liquid - not neat because that was too thick - so she diluted it to make a runny liquid. Her balls grew to the same size if not a little bigger than the ones in water. She has sent us away thinking about why!!
|( great montage taken by class teacher!)|
This is an example of a class write up - I love the narrative especially the comments about using vinegar! A great example of observation and thinking through changes - well done.