Ok, I just found out that despite it not being written down anywhere in the school handbook or anywhere else, it's apparently against my school's policy to have any mobile device even capable of running games, regardless of what it's actually used for. Furthermore it's apparently against school policy to do anything BUT school-related stuff at school. They don't care if you're done with all your classwork. I actually had a teacher say to my face "If you're done, it means you haven't checked your work enough times."
I loving hate the school system. It's so borked up.