[Madhatter]

I've used a fair bit but not the real fancy stuff.
7*7 is a hard sum to work out really unless you know your tables because its an odd times an odd.

Adding up whole shopping bills where something we used to do when we got minimum spend vouchers, ie 4pound off when you spend 20. Excellent way of keeping your brain active.
it's also not just learning it you see, it's learning it and using it to keep it learnt. Brain cells die off all through our lives, and word and number puxxles help to slow the process.

Calculator should only be used in schools as they were in our day, only as far as need be to teach people how to use them, how to work out percentage with a percent key, and without a percent key, and then add it back on etc.
How to use the fancy button, profit margins ad mark up etc.

Tills. hmmm I once had an argument with someone in a cafe about my bill. She rang it up, gave me my change and i sat down. I went back and said this isn't right, she went through it and said it is. I said it can't be.
Anyway, I sat down ate my food and worked it out as she suggested i should, and then I'd see it was correct. It was incorrect. The change she gave me was right based on what the till said she should give me, but the till added the actual items up wrong 24 plus 24 does not come to 54, therefore it was wrong .
Goes back to the girl, goes through it, she says "there now can you see its right", NO, Goes through it again,NO ITS NOT RIGHT, YOUR TILL IS WRONG.
She gets a piece of paper writes down the items, like I'm being totally thick, and hey presto. lol the look on her face. I accepted her oppology as it was so obvious that she put so much faith in her stoopid till she would have trusted it with her life so therefore she would never have believed I could be right.