It’s easy to have a list with a bunch of prestigious and/or well known universities and I’m afraid I’m overlooking universities with challenging academics that also foster a culture of learning just to learn and understand more about the world around us. Any suggestions big or small are appreciated. Thanks!
You probably want a LAC, small enough to foster a sense of community. My D17 will start at Colorado College in the fall so I can’t say for sure, but she strongly believes that this is one that supports intellectual curiosity over competition. Others that she looked at (because this was important to her, too) were the 3 up in Maine, Hamilton, Haverford (too small for her though), the Claremont McKenna consortium, Vassar, Tufts.
Thanks so much for the suggestions! LACs seem to be what I gravitate toward, and I like the idea of smaller schools, very helpful!
Definitely look at Reed in Portland.
Oberlin, Reed, Kenyon, Bowdoin, Grinnell, Lawrence, and particularly Pomona of the Claremont consortium.
Oberlin, Kenyon & Bowdoin were suggested by my college counselor too! Thanks so much!
I’d echo Reed, and throw in Bard as well.
Not an LAC, but U Rochester has their Take Five Program. You apply for a fifth year, tuition-free, to study something unrelated to your major, just because. 
http://www.rochester.edu/college/CCAS/students/opportunities/takefive/
For reasons partly, but not literally, related to the included link, consider Reed, Carleton, Grinnell, Hamilton, Swarthmore, Middlebury, Wooster and Bowdoin:
https://www.princetonreview.com/college-rankings?rankings=students-study-most
Williams could also be excellent. Seconding the Vassar and Kenyon suggestions.
Agree with all the suggestions above. Throw in U. Chicago as well. Any list of “Ph.D. feeder schools” should give you great suggestions.
I think open curriculum schools would interest you. A few (Hamilton, URoch) have been mentioned. Brown is another. I’m in the northeast so not sure about the rest of the country.
Carleton, Pomona, Reed, Grinnell, Haverford, Kenyon, but all would be reaches for everyone.
St Olaf, Earlham, Beloit, Wooster, Lawrence, Dickinson, Skidmore, would be easier to get into.
Check out schools on the following 2 lists:
https://www.reed.edu/ir/phd.html
http://ctcl.org/category/college-profiles/
Schools on the first list tend to be more selective than schools on the second.
I second Brown. No one has mentioned University of the South (Sewanee.) Also, Emory, UT-Austin, Rice and Tulane are examples of big, DI football powerhouses where nerds and intellectuals are still valued.
Reed, Chicago, Grinell, Oberlin, Brown
My kid had similar criteria. Her list was Swarthmore, Harvey Mudd, UChicago, Carleton, Kenyon, Macalester, Mount Holyoke, and Lawremce. And she liked Reed, too.
Tulane is notable for its emphasis on interdisciplinary studies. The school makes it easy to combine majors for a focus incorporating more than one field of study. 70% of Tulane students double-major.
Emory is a D3 school without a football team. Rice and Tulane can hardly be classified as football powerhouses.
I seriously believe that the OP is underestimating the culture of learning for the sake of learning at many prestigious schools. I work with a lot of recent UCLA grads and with the exception of the bio and biz econ majors, they would agree that it is extremely intellectually challenging.
You may be right about Emory. The point I was trying to make was that there are large, complex, universities out there with little resemblance to LACs, where the intellect is nevertheless valued.