I don't think I recall anything particularly useful from school cookery lessons - too formulaic (and my father, who had school cookery lessons during the war, is certainly no cook!).

I learnt my cooking from my mother, and she was always worked from general principles, telling me, not just what to put in, but what the function of each ingredient was, and basically how and why everything worked. So I can adapt recipes and know what I need to do to counteract any ill effect of substituting any of the ingredients, and I can create a palatable dish from whatever selection of things the pantry and garden happens to throw up tonight.

I've used the same approach when teaching my children, both of whom are competent cooks in their different ways.

Trouble is, we seem to have broken the link (just as we have in gardening) with a generation that bought into the whole convenience food ethic and now in turn are unable to teach their children because they've never learnt themselves.