Teenagers are sexually driven creatures. I think that people are constantly driven by nostalgia to say that it's getting worse and worse, but really I don't think things are much worse than they were when I, my parents, or my grandparents were in high school. In my grandparents/parents days, teens still got pregnant, they just went on "vacation" for 9 months and came back sans baby or with a new "baby sister/brother." Or they'd just get married at 14,15,16,17,whatever.
When I graduated 5 years ago, 16 of the 23 girls in my high school class either were pregnant or already had kids at graduation, and this was in a very, very small Baptist town that had no sex ed class (the parents objected and the principal, a Baptist deacon, agreed). So it is my opinion that religious, "abstinance only" education will not work on most kids. Those who are committed will save themselves, but you just won't be able to convince a majority of kids to remain abstinent.
As to getting picked on, I'm really sorry. I know it sucks. But you have to realize, too, that EVERYONE gets picked on in high school for one thing or another. I was picked on because I was one of the "smart kids" and because I was tall. My sister is picked on now for the same reasons. With high school/middle school, it's not so much a matter of "will I get picked on," it's a matter of "what will I get picked on for?"
Either way, good luck! Once you get out of high school you'll realize how little those years of your life mean in the scheme of things, even though they seem so important right now. Just please yourself, do what you think is right, and you'll come out much better in the end.