Harry Potter based interest check
So I'm getting this idea that there is another wizarding school (name and location undetermined), only this school sorts its students into houses based on area of study after 4 years of basic training. (i.e. Transfiguration House, Potions House, etc) What I am having trouble with is creating the "catch", the main plot, I guess you can say. I would like to avoid "Voldemort has returned / someone has followed in Voldemort's footsteps" story if possible, so I'm asking for some creative ideas here.