I am in 6th Grade, and here are some tips:
1. Work will be harder: Yes, some people have got 60's on their math tests, and the worst grades in my school go down to 10-30s. You have to study, and pace up now. Also, there will be more homework and less free time.
2. Pay attention: Take constant notes in most classes. If you don't, you could get bad grades.
3. Know that there is more walking around the campus, unless it is online.