I think at my high school, the highest level course was calculus I and II, and physics I and II. They may not have offered any physics courses at my high school, but some classmates in college said they took it. Then again my professor from Poland said they taught him physics in 4th grade.
Do high schools anywhere teach more advanced math and physics? Does it vary regionally or do they usually stop there?
Where I was from, if you wanted to take courses more advanced than this you had to take them at the local college and do half days at high school.