It's an interesting thread, and I want to comment but i'm afriad to in case I get my head bitten off by a CSS / validator type person. But I've decided to go ahead anyway!
The balance i guess has to be, as has been stated, between adhering to the rules, and keeping things exciting. Personally I think if you tell an 11 year old that if he wants to make a website then he needs to put in all that code that, as far as they're concerned, doesn't make a difference, they're going to be put off. I'm afraid I don't subscribe 100% to the apparent view that if you do it wrong then it's not worth doing at all - "Plus, we have too many people already making non-valid sites, we don't need more" - I just dont agree. certainly we should aim to be compliant with the standards, but i think we should be wary of scaring people off at a young age by cramming rules and regulations down their front - kids hate rules and regulations!
I guess i feel that there's an element of snobbishness that had developed as a result I guess of so many "DIY" packages and people who have a go - what some people see as a true triumph, that people can just have a go, make a crappy little site with animated gifs and background wavs and the like is great: people soon realise that it's bad, and then fix it, go away, learn a bit of CSS, find out about validators etc and try to adhere to the rule book. But you cant start out that way!!! That'd be like trying to teach a bunch of kids soccer, and spend all day pulling them up for being offside, dangerous tackles, back passes - noone does that. Kids learn to play soccer through having a kick around in the garden. Similarly with maths, loads of kids will do exercises at some point that look a bit like:
3 + = 7 + 4 = - 2 = __
where they have to fill in the gaps thus:
3 + 4 = 7 + 4 = 11 - 2 = 9
but that statement, mathematically, is wrong! it's not correct - and yet we use it because kids enjoy it and as such stay with the topic. Eventually you get them round and explain it and how it's actually a form of algebra, but people adapt - only the very lazy don't, and i think that's one of the misconceptions that seems to be running though this thread.
In short, just stating my humble opinion, but i came to the wonderful world of web programming by messing around with front page, finding out that it couldnt do stuff so working in notepad a bit, then moving to notepad completely, then finding out about java scripts, then about asp's, then CSS's, then PHP. i can turn out some good stuff (even if i do say so myself!), and i can make a little money from it, but i'm always trying to improve what i do by learning more and correcting my mistakes. I think it's wrong to think that kids wont be able to do the same, and to think that the only way to teach people things is to sit down with the rule book .
They're kids - let them have a kick-a-bout. :p