The above list by tk21769 is a good one. When touring smaller colleges with my kids I’d always head off to the art museum to get a sense of the school (my kids would go in a different direction to get their own impressions 
) and was immensely impressed with so many of them. Vassar and Brandeis were personal highlights but Bowdoin, Colby, Skidmore, and Smith were also great. Of course the granddaddy of them all is the Yale collection.