Your sOn should pay attention in class, do all required homework, studying & behave appropriately in a school evironment, whatever grade he is in. It'll be the same as it was in grammar school -- it's only a different grade and/or building. Good academic & social behavior rules remain the same.
No drugs, alcohol or any talk in the works about bad ideas and plots in the works. They watch you like a hawk! But definitely pay attention and keep your average in your academics up because come high school, lots of students grades can be in critical condition as to them graduating. Just be the respectful student who comes to school ready to learn and who goes home and has a social life after what matters, and that's school!!