Apart from some rather obscure chemistry lessons (making blue chrystals, something to do with copper - but even so I know they turned blue, which could be useful in a quiz)) I can't think that anything from school has been useless. Not being a mathematical prodigy I thoroughly enjoyed lessons on trigonometry by drawing the ship at sea, lighthouse etc.. (I did Art, History and Eng. Lit. A level.) Imagine my surprise when, after a bit of head-scratching years later, I found it came in useful! I really believe tables should be learned by rote (once you know what they mean) because most of us are not mathematicians and simply need to be able to use arithmetic every day in countless situations. There used to be a CSE Arithmetic exam, which was so useful to pupils that of course it was pulled out in favour of Mathematics GCSE. I gained starting points into all the academic subjects and the knowledge of how to investigate further, hugely valuable as it's turned out. What happens when the electricity and the internet fail - it's possible with cyber-attacks? People need to actually know things, not just how to research.