You know, I could do the usual thin and call the person a n00b or a lamer, or something. I could "give them a link" that points to google, and feel really clever. I could tell them to learn c, and then read a bunch of RFC's, and learn tcp/ip. I could tell them that hacking their school network is wrong and immoral and whatever, but its just so .... been done. Sometimes I et the feeling we're just kicking a dead horse here. So, instead, I'm going to tell you exactly what you need to know.
figure out what services are running on your machine. This should be trivial to do, and if you really get stuck, install nmap and then do
nmap -sS -sA -v -T5 localhost
write down all the services and version numbers
go to packetstorm or security focus and look for local privilage escalation exploits for the services that you just found. Keep in mind that many of these exploits are "skiddie-proofed". That is, they have made minor modifications to the code to keep it from compiling or running. So, you will ned to know enough of the chosen language (usually C) to fix the exploit. Once it is all set, compile, run, root. There, you are now a 1337 hax0r. you are k-rad. Have a nice day.