Fiction for young adults and teenagers is a relatively new invention. Until recently, teenagers were considered adults and expected to read adult literature. It wasn't until the 1960s that authors began to realize that there was a gap in literature. We had books for children, up until about age 12, and books for those 18 and older, but nothing for the 13-17 age range. Young adult fiction sprang up to fill this hole.
Writing Fiction for Young Adults
Writing for teenagers can be tricky. It's too easy to assume that because they're young, they don't understand complex subject matter. This is far from the truth. Their interests might vary from adults, but they are just as smart and just as deserving of respect as adult readers. Take this into account when writing a young adult novel.
It's also tempting to pick the current trend or fad and use that as a basis for your book. Bad idea. Teenagers today are growing up at an extraordinary pace, so by the time you finish writing your book, the kids will have moved on and you'll have difficulty finding a publisher to take you on.
When writing fiction for young adults, younger characters should carry the story. Your principles should be 13-17 years of age so your readers can identify with them. You can certainly have characters older and younger than this, but try to have those characters who drive the plot and solve the problems as close to this age range as possible.
There are some things to avoid when writing for young adults. Teenagers are exposed to everything from drugs and smoking to sex and alcohol. However, that doesn't mean they things have to feature in your book. Try to make your characters into role models when dealing with sensitive topics. Don't imply bad behavior is okay, even if some of your characters do deal with some of the problems listed. Try to think of what you'd want your own children to read. This doesn't mean you can't have characters having sex, but you have to deal with it tactfully. And, for the love of all that is holy, do not have a graphic sex scene! It simply doesn't belong in a book for teenagers.
The other dillema you might encounter is the use of slang and profanity. In general, you should avoid popular slang. What's popular today could be gone tomorrow, so slang may simply date your book and limit its appeal. As for profanity ... it's probably better to not use it at all, or to use it sparingly. I know a lot of teenagers use excessive profanity, but not all of them do. Those who don't will be turned off and toss your book in the trash heap. Those who do are usually smart enough to read books that don't rely on the shock factor of profanity to entertain.
Other than these things, fiction for teenagers is basically like fiction for adults. They like fast-paced stories that engage and entertain. They also like a variety of genres, so don't confine yourself to the typical high school setting. If you like to write fantasy, write fantasy. If you prefer a good mystery, go right ahead. Teenagers enjoy a wide variety of material, just as you probably did when you were a teenager. With that in mind, go wild! Within reason.