This is a capacity lesson based on Harry Potter. You will need some containers with various liquids in. I used water with food colouring. For the broomstick salt and wand powder, I used Gellibaff and crushed up bath bombs so that they reacted with the water like real life magic. The tasks are designed for Y2, but can be adapted for any primary age.
If you have any questions about the lesson itself, please ask!