I'll bet you're taller.
Seriously, this would so easily be handled by addressing behaviors instead of attitudes. Simple rule: "Everyone, teachers and students, will behave politely toward everyone else at all times." If you want to "hate" someone because he's black, tall, short, smart, or homosexual - fine, hate him, but you'd better behave politely at all times, or you're (detention, suspended, expelled, in quick sequence.) No worries about "respect," "tolerance," or any other mind-control nonsense.
Awww, that wouldn't be any fun. The guidance counselors wouldn't get to counsel students, the consultants wouldn't make big fees running workshops and assemblies, teachers wouldn't get to turn in students on a whim, parents wouldn't have to go crazy finding out what degree of intolerance was alleged and determining if their darling actually did the alleged deed, books couldn't be written about tolerance and diversity, lawyers wouldn't be hired to resolve these issues or sue the school, and the hiring of additional school personnel to handle all this wouldn't occur.
See, you'd put a lot of people out of work. No, we can't have this.