AP course differences in schools.

Well obviously AP courses focus on the material that is projected to be on the AP exams. So each class, whether it be in a public or private school, would generally have the same material (I suppose). At my school it is not recommended to take more than 4 AP courses a year, and I have taken half of one and I can see why! The reading I had in that class was very intensive (my teacher was infamous for difficult tests) and I had to devote a lot of time to my work to ensure I would do well. I will be taking two more AP courses next year (senior year) mixed with other honors courses, and I feel, with my extracurriculars, that it will be difficult but manageable.
But when I see kids asking to “chance them,” a lot of them have taken all APs! And 12-15 career APs! I devote a lot of time to every class and I cannot fathom how one could handle all of that! My school (parochial) doesn’t even offer 12 APs and taking anywhere near that many would be considered absurd and unmanageable. So my question is, if APs are supposed to be the same (very challenging) material, how can one take that many at one school and manage it but have no chance of doing so at a school like mine? Unless some schools’ AP classes aren’t as hard, which if it’s the same material, i find it hard to believe. Anyways, please respond! I am mighty curious! :))

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