Does a college have a legal obligation to offer advertised courses? If a US college/university advertises itself as having a certain major, with supporting courses, are they legally obliged to offer the courses or similar ones? I am thinking of a new program where the school planned to hire tenure-track or adjunct faculty but did not do so. Instead, they tell students to cross-register at other institutions (which costs additional money) or take online classes to meet the requirements. Would this be illegal?
Disclaimer, I am not a lawyer.
If the college/university doesn't offer advertised causes, the obvious law it could be breaking are those related to false advertising. US false advertising laws say that for a successful case, one needs to prove five things:

The advertiser made false statements of fact about its product;
The false advertisements actually deceived or had the capacity to deceive a substantial segment of the target population ;
The deception was material;
The falsely advertised product was sold in interstate commerce;
The party bringing the lawsuit (plaintiff) was injured as a result of the deception. Injury is construed as a likelihood of injury, rather than actual injury.

#1 seems trivial given the assumptions in the question. #2 should also be trivial. #3 reads rather vague to me, but if it means (as another source says) &quot;the company lied about something important&quot;, then the plaintiff must show that they went to the university because of the advertised courses (or perhaps they can show that the courses available are a big part of the reason they went to the university, as opposed to say convenience). IANAL, but this seems pretty trivial as well since it's hard to argue that a university's courses aren't important in the university experience.
#4 deals with &quot;interstate commerce&quot;, which means &quot;any commercial transactions or traffic that cross state boundaries or that involve more than one state&quot;. If the college/university only took students from its own state, it should be fine. For every other case this should be trivially satisfied. Finally, #5 says the plaintiff must show that they were hurt by the deception. If one were e.g. hoping to become a particle physicist and it turns out the particle physics course was not offered, then this should be clear.
So yes, if the college/university advertises a course they have a legal obligation to offer it.
The scenario you described is different. Does &quot;offering&quot; a course mean they have to physically offer a course as opposed to arrange for students to take it from another university? One can certainly argue it doesn't - after all instruction is still being offered. Some advanced courses will even say they are only offered subject to student interest. Further, unless the university actually advertised the courses as being taught on campus, their advertisement wouldn't even be wrong. There are laws against misleading advertisements too, but it is not clear that courses have to be taught physically. Certainly during COVID many classes are taught online, and if false advertising claims have arose from this I'm not aware of it. It is possible one could still argue hurt because one has to pay cross-registration fees, however.
tl; dr: IANAL, but I suspect if the college makes arrangements for its students to take the advertised courses either online or at another university, they will be in the legal clear.