Yep, adding to what Sharkfin said, my immediate thought was also conduct requirements tied to federal aid - namely, if you are convicted of a drug crime (specifically drugs, which is notable), you can no longer receive certain federal grants or scholarships and may be required to pay back what you've already received. To answer your follow-up, no, the federal government generally cannot and does not weigh in on admissions. This is why even people without legal papers can often enroll in US state universities, and even receive financial aid and in-state tuition. Requirements for admission are set by the school and influenced by the state. Universities can choose not to admit someone for many, many reasons. Having a criminal record absolutely does not (and should not) preclude you from higher education. I have attended classes, in a prison, through a program that specifically seeks to educate those who are incarcerated. This could be a cool area to investigate further - a case related to providing higher education to the incarcerated/formerly incarcerated would hook me quickly, or a case that changed the drug crime funding rules. There are several university debate programs that sponsor prison debate programs, too, which are awesome.
Most universities are attuned to state, not federal laws, and care mostly because they receive state funding. You'll note a lot of Department of Ed materials specifically note they do not accredit or otherwise really regulate major universities. Private universities like Harvard that have massive endowments may ignore some of these state laws, and smaller private universities, like a number of Christian ones, may eschew state funding altogether, including aid for students, if it's tied to conduct rules like Title IX. As Title IX is a federal law, that might be one avenue of exploration.
As a regular undergrad student, you'll likely not be aware of most of the state/federal/local administrative machinations of universities. As Sharkfin notes, student conduct codes, dorm rules, and other university-specific regulations hold far more of your attention. I can't say the no pajamas in dining halls is a common rule though, at least based on how my students come to class.
But yes, overall you are treated as an adult who is expected to regulate your own actions, minus some particularities in dorms and classrooms. Remember too, that as state-funded properties, state universities are very open to the public, especially libraries and unions which are clearly public spaces. So not everyone a university is dealing with is an enrolled student, and members of the public have not consented to things like student codes.
That's quite the wide-open resolution, as is NCFCA tradition. I'm intrigued by the lack of actor (generally USFG), and would encourage you to look at national accrediting agencies as possible actors under this wording. The 50-states plan/CP will also be big this year, I feel, and as a judge I'd be willing to listen to an argument that changing less than 50 states' policies is also valid (26 or more? it's open to discussion re: significantly). I could even see an argument for changing one large system, like making a change to all California/New York state schools, as substantial if a decent modeling argument can be made (e.g., California makes a change to its ~30 schools that other states will follow).
Here's a couple of links I think will be helpful in generating case ideas:https://www.rit.edu/fa/grms/fed-laws-by-alphabethttp://www.higheredcompliance.org/matrix/