I am in my final semester of college right now. A couple of weeks ago, I was contacted by a school district near me that I was an intern for a previous semester with a long term sub position opportunity starting in late winter. I was excited because I thought I wouldn’t have anything lined up until august, so I unofficially agreed and showed interest in the position. However, I got an offer to be a GA for my master’s program that would be a way better opportunity for my professionally and financially (I was worried about finances as a long term sub). This does leave me worried that if I back out to be a GA, I will upset the district. I’ve also heard that admins of different districts talk, so I’m afraid I’ll also hurt my job prospects after grad school. The thought of abandoning the position is also making me feel a little guilty, even though I know it would be the best decision for me. Would it be too unethical and unofficial to back out/decline the long term sub job since it is still a few months away and there was never any official documents signed?