Er... I'm on the fence. The idea of the character is something I like, but... the graduation age for the Academy is 24... It doesn't make sense to me that Thor would put his adult son into the school for one year and expect him to pick things up that fast. Maybe if you dialed him back a few years?

Also, "slightly weaker" than Thor is still probably enough power to take down a whole army... 

The concept is good so far, but you'd need to reduce his power a lot before I could give my thumbs up, sorry.