Only thing i can tell you is keep trying.If you give up you won't go anywhere.
Read NullByte , forums, youtube, as much as you can , and once you will master something you will have motivation to keep on.
I'm sure that your question has been answered in other threads, so search the forum.
From my experience is charge right into the fray of things... you can't learn everything but jumping around until you get the jest of the art than go on there. I personally started out by learning how to hack my mom's WiFi so that I could get the WiFi password. It was nothing big but it got me started. Pretty much read, read, read, and type a lot but eventually you'll get there. :)
I'm sorry to say that learning how to hack is a combination of trial and error learning, as well as book smarts. What you will learn in school is the fundamentals, the building blocks, of hacking.
I feel like this is something you will need to put more effort into doing; as frustrating as it may be, this will not happen overnight. By all means, go through the tutorials here and learn, but I suggest that you learn everything your school has to offer you.
For now, I would recommend you read my article here. It has several helpful links for newbie hackers to Null Byte, as well as general guidelines for how we do things around here.