At my school, the AP chemistry teacher has an extremely high AP average, but it is extremely difficult to get an A in the class. On the other hand, both Physics 1 and Physics C have lower AP score averages with my school compared to AP Chemistry, but it is much easier to get an A. I was originally planning on doing AP Chemistry junior year then AP Physics C senior year, but now I am debating whether or not I should do AP Physics 1 as a junior then Physics C as a senior, or Physics C as a junior then AP Biology as a senior. (I am currently taking Calc BC junior year, and I can’t do the AP Bio assignment in four days so I can’t transfer in.)
If you’ve had a physics class already, Physics C as a junior, Chem as a senior.
Just be sure you take bio, chem, and physics, and one of those as an AP. Personally I would suggest AP chem this year and physics C senior year.