I think most college instruction in the U.S. is now online. My eldest child, studying computer engineering at a large public university, had 3 out of 4 classes online last semester and will have all 5 online in the coming one.
Colleges have determined that Zoom classes are good enough to warrant academic credit. If so, high school students should be allowed to enroll in college classes they are prepared for, and the credits they earn should count towards a college degree.
The most prestigious U.S. colleges reject most of the applicants who are qualified to do the work. They have resisted expanding their enrollment due to limited dormitory and classroom space (and to maximize prestige based on scarcity). Harvard's
Math 55 is a famously difficult course for ambitious math majors. Currently, whether you can take the class for credit depends on getting into Harvard, which in turn depends not just on grades and test scores but on your ability at a sport, on whether your parents are big donors, on your race, and other non-academic criteria. This should change.
Interesting that you mentioned Harvard and Math 55, both of which I know well.
My child attends Harvard. He was admitted despite not being the least bit athletic, nor a donor, nor a member of any preferred racial or economic group. While I agree with you that college admissions is not "fair", I also know it is possible for unhooked kids such as mine to gain admission to the most elite schools, and I have offered free admissions advice on this forum to anyone who wants it.
My son was actually admitted to several of Harvard's peers as well, and a major reason he chose Harvard over the others was Math 55. If there is one class that really isn't meant for the general public, it is this one.
It is hard to overstate how difficult this class is, and I suspect that no more than 100 people nationwide are capable of passing this class. My son wrote four mathematics research papers in high school, including one that was published in an Elsevier peer-reviewed journal, and another which received major recognition prior to publication. Despite this extensive math background, even he needed about 20 hours per week to excel in this class. And he feels that some of the people taking the class really shouldn't be there because they need to be hand-held by the teaching fellows (called TAs everywhere else).
