Here's my 2 cents.
I fully support the idea of sex education in schools. I had my first sex education lesson when I was 8 and I feel that it is important to educate children about the importance of contraception and the dangers of STDs.
Personally I lost my virginity when I was underage, I have no regrets about it just who. It just happened and nothing ill came of it. Now I am 18 I realise how young I was and feel a little shocked looking at the 13 year old girls now. I also believe that having sex with one person and breaking up does not make it any less special when you have sex when you find Miss/Mr Right. I also feel that having sex with more than one person in a short span of time does not make you a 'slut', it's an innapropriate label if both parties are consenting. What does make you a 'slut' is playing 2 people at the same time and cheating on someone who trusts you. Threesomes, foursomes and moresomes if that sort of thing floats your boat I'm a-okay with if it's all clear with both parters involved. I'd be far too shy for any of thoose.
It's all down to the individual, some teens are mature enough to handle it I know from personal experience as I have had no negative effects from it, some, like a friend of mine, don't think and end up catching something.