What are some unethical high school hacks?
I guess the most obvious one that isn't technically the obvious cheating (getting work from previous students, sharing answers etc.) would be the website quizlet. Absolutely a life saver. Most of my teachers are too lazy to create their tests themselves (and even if they are more motivated, previous students of that teacher may have put the tests online) Take the first question and type it, word for word, including all the answers (if it's multiple choice) into google. If you're lucky some kind soul may have made a quizlet for that test, or there may be a pdf of it off some educational website (some more sketchy than others so as a rule of thumb I would recommend not giving them your credit card number, no matter how enticing the one dollar answer key is)
Way back in high school sophomore year, my best friend and I learned the ASL deaf alphabet and were able to chat clear across the classroom, even during tests. It looked like we were just exercising our fingers but a lot of data was moving across the room. ;-)