[TOMT] [MOVIE] [SHOW] movie/show about teacher working undercover for a bigger bad?

i literally cannot remember this for the life of me. can’t remember when i watched it either 😭 but i think it was fairly recent. all i remember is the teacher was new, and he had paper cranes on his desk which were meant to symbolise that he was the bad guy/that he worked for the other bad guys? i literally cannot remember anything beyond this, i just have a vivid memory of paper cranes on the teacher’s desk and that’s about it 😭