Re: FILTER.
Of a sort, but not in the sense you're thinking, I think. I went to a boarding school for witches and wizards during my teenage years to learn how to use my magic properly and there were four houses - Gryffindor (the best), Ravenclaw, Hufflepuff, and Slytherin.
Based on your personality type, you were sorted into one of those four houses, where you lived with likeminded individuals for your duration there. My family tends to be sorted into Gryffindor, but it's not a rule. The sorting also heavily takes your wants into account.