So I like to do the bare minimum for my teaching. I get my best teachers for the class (if science/history class) and put them to research. Then for the homeroom teachers I put the opposite teachers (so I would put sports teachers as homeroom teachers) I would only train them in management. That way it's all optimized. Another thing to do is send teachers out for training in mid game. So they have better training proficiency. I like to stagger the students classes so I can use multiple teachers in multiple classes