Ninth grade is the first year of High School for many people. It is (for most people I would say), the last year that you can still be a kid. Once you get into 10th grade people start driving, working, and having sex. Of course I am making sweeping generalizations here, but I think you know what I am talking about.
For me 9th grade was the year I got my first girlfriend, and it was the first year that no one beat me up (not even once). I would have to say that 9th grade is the only grade that I don't have any traumatic memories attached to either.
A few tips for 9th graders.
When they try and make you take biology say no. Unless you really plan on 4 years of science. Science is a fun and wonderful thing, but the facts of life state that you will probably end up being some sort of desk jockey or pizza delivery driver. Very few people actually get to shout "EUREKA!" in their secret laboratories anymore. That stuff kind of died out at the dawn of the 20th century.
If you are scared of the opposite sex but still want to try, just pick anyone who is quiet and has glasses. If you show some interest they will probably like you. So many high school students are obsessed with the "hot" girls, and don't even notice the other ones. Now that I am well out of high school I can say very truthfully that the other ones are really cute too. Enjoy them all, while you still can
Don't buy any Elevator Passes from anyone. If your school has an elevator, then the chances are good that you are not going to be able to use it. There are no magic passes. So don't buy them!
If you join all of the clubs you will be able to get your picture in the yearbook over 30 times.
More important than all of those is that time honored advice of "be yourself". Seek out people with similar interests. Don't get down on yourself if you don't make it into the popular crowd (they are all weenies anyway).
" versions of classes don't actually mean anything (but generally draw a higher quality of person). Have fun, you still have your whole life ahead of you.