Obviously, new Toa would get mentored by older Toa and schools did exist in Ga-Metru, but your idea of a Bionicle High School is very goofy. First, there probably would never be enough new Toa created at once for a whole school dedicated for them. Second, Bionicle is a story about adventure, saving universes, and you want to see it turn into a teenage social drama with jocks and valedictorians?
So how would the teachers ensure that their students remember anything? Just hope that they don't forget their lessons by the time they need them?
Why would wise, calm Onua, and cheerful, friendly Pohatu be jocks? Why would Tahu, who is literally a hot-headed macho jock, be a valedictorian? Why would the Toa Nuva even be students instead of teachers? I'm very sorry, but are you familiar with these characters at all?