I would take a look at T20 liberal arts colleges. They’re rarely listed together with the usual research universities (Ivies, Stanford, Caltech, etc), but have impeccable resources because they have the luxury of focusing on a small number of students. Their acceptance rates are often twice as high as their Ivy counterparts. Recent Apker Prize winners have included undergraduate work by students from Wesleyan (CT) and Williams (MA):
https://www.aps.org/programs/honors/awards/apker.cfm