Firstly, we created 'Red Cabbage Soup' linking it to Charlie and the Chocolate Factory. Once we had the soup we strained to cabbage. by doing this we created 'anthocyanins. These change their colour depending on the PH of the solution added. 

The children had their own substance and had to guess if theirs would be more acidic or more alkaline. 

Why not have a go at home, see if you can create some potions of your own.