Well, I'm personally happy that someone finally posted this thread, because it allows the answer to be in one, comprehensive place.
1) Prank Calling:
Prank calling in the US can constitute harassment. However, if you don't make any threats or do something that could be proven to either A) Cause someone harm or B) Cause a business to lose money as a result of your harassment, you're not likely to be prosecuted. Any time you start repeatedly calling the same people and businesses, that risk increases, especially if you get warned once by either your local authorities or the phone company. If someone feels you are making harassing calls, they can *57 you, which performs a "trace" and allows the phone company to record you as a problem subscriber. If those traces start adding up from the same numbers, then your parents (or your friend's parents) may get a call or letter from that phone company. If it's really bad and repeated (and a lot of people complain) the telephone company COULD turn that over to authorities. I don't have any recorded cases of that happening where it actually turned into charges, but you never know.
I am, however, not going to give you suggestions on how to decrease the risk of getting caught. You'll have to figure that out on your own.
2) Redboxing
When I was in high school, I boxed pretty constantly for about 2 years. I had quite a few close calls with the phone company, with security at businesses (I was dumb enough to start boxing from a bank of phones at a mall), and I even had a brush with real police. If you get caught with a red box or a device that authorities could prove is made or modified to produce coin tones, then it's toll fraud. I don't remember if that's a felony; you might want to look it up. If the police look at your computer and see that you've been visiting sites like phonelosers or any other "hacking" sites, they can also ban you from Internet access until you're 18, which sucks.
For both of these, if you get caught and prosecuted, you're looking at community service, probation, possible state counseling, or (depending on your community) a short stint in a juvenile facility. Since you're a minor, your name probably won't be released, but word gets around. Depending on your school district and state, you may also have to sit an expulsion hearing with the school board to have them determine if you're a danger to the other kids in public school (this is much more likely if you actually get sentenced to do any time). Even if you don't have to, your parents may just pull you out of public school anyway.
