Some teachers, man, they just don't get it.
I used to play mobile games on my smartphone, but then I took a graphing calculator to the face.
Youtuber no9sniper brought Skyrim to his TI-84 graphing calculator. It's obviously a bare-bones, mostly text version of the vast and sprawling world of the original, but it still features basic items, quests, and combat with a variety of mythical uglies. Perfect for when your math teacher starts to complain about you bringing your widescreen hi-def PC monitor to class.