Bear had a maths tutor lesson yesterday, but they didn't do maths. They did science. Apparently you can use juice from a red cabbage to measure how acid or alkali something is.
Bear loved it, he really, really loved it. They tore up the cabbage, poured hot water on it and then whizzed it up in a machine.
Bear was amazed as they carefully and scientifically added the contents of mystery containers to see what would happen. I was mortified he didn't recognise the smell of lemon juice but not surprised he didn't recognise bleach. I'm scared of bleach in large quantities and use milder cleaners - also I am a rubbish housewife. He watched with delight as the colours changed in front of him.
By the way, did you know that if you add dry ice (solid carbon dioxide) to something it makes it more acidic. We watched the colour change and special effects. It was amazing. Bear is a very lucky bear. I am also lucky as the maths tutor was kind enough to let us wait for a while before DH could pick us up. She is seriously brilliant.
The spooky mist from the dry ice isn't very clear, but you can get the idea. It rocked!