Great minds, linzer - I already use that site (and the bingo generator) for all my flashcards.
English happy families is a great idea, but I don't think it will work with my predominantly age 4yos, since getting them to repeat a whole sentence in English is quite a struggle. I'm currently doing family members with the older group, though, and it would make a nice change from bingo (though I agree that goes down well).
I assume the other kids can see the coloured backs, but not what picture is on the cards? Do I need as many complete sets as children in the group? Presumably the kids take turns round the group, but can ask any other child for a card when it's their turn?
Thanks everyone for recommending blu-tack. At least my parents are coming next week, the last time I looked for it here I found it very difficult to source (was about 10 years ago though). I still can't decide whether it would be better to make eyes, nose, mouth, ears, hands and feet for the kids to stick on, or an arrow. It would be fun for the kids to try to identify the shapes while blindfolded, but it wouldn't let me practise shoulders, knees, fingers, toes with them. Otoh, I will be doing "head, shoulders, knees and toes" with them, so maybe it won't matter.