You mention the maths, but what about core subjects like geography, history, english lit?
The upper level courses usually combine stuff. I.e, AP Humanities combines lit, geo, and history together rather than split them out. Or, they offer electives that cover other areas, ie Chinese History, etc, that add stuff in.
Some schools are now pushing to reduce class loads, ie making students take just five classes rather than six so that some stuff can be added in to the core classes.
And don't forget the AMC 8, 10, and 12 tests. Some schools still don't know what these are.
