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Can college/university itself be considered a valid nomination?

I'm talking about general colleges and universities.
Answers
Yes. All of them for adults. Universities, colleges, professional institutes.
And what would be the proxy object for the location? Personally, I find it a bit of a stretch of the "educational value" criteria (btw, what happened to all the examples that use to further explain that criteria?). If there is a historical marker, and many colleges and universities will have one, then that would definitely qualify and would also serve as a proxy for the college/university as well. Example of one below.
Watch out for K-12 and 'College' having different meanings in different countries though, a college for 16-18 year olds would not be allowed.
Yes College in France is for under 18s - even more confusing in the UK 'Community College' can be another name for a secondary school or it could be a Further Education College focused on adults.
Signs for college buildings are acceptable too.
What criteria do they meet?
Do they have historic value that doesn't involve them just being old?
What makes them stand out from other colleges and universities?
And are the colleges strictly for 16-18 year olds like some in the UK are?
Alternatively, you could find stuff to submit on the college/university grounds such as statues, plaques, etc
Colleges and universities are centers of higher education as well as gathering places for the community. They absolutely meet criteria on those grounds. Every college or university I've ever been to (and I've been to many) has a large entrance sign (often with accompanying display) that would serve as the proxy for the whole college or university. Furthermore, you can usually find a wide variety of art, educational displays and educational buildings on a university/college campus - all of which meet criteria on their own.
I am using the term "college" in the North American sense - a place for post-secondary education of young adults (ages 18+).
Generic college, no real rich history. Just the building and it's name used as title nominated as a POI.