Just a quick reflection on this relatively minor point. The winter weather will be fairly different between the three with Haverford being relatively mild (comparatively), Grinnell being fairly cold, and Carleton being truly, brutally freezing in the winter.
Average highs/lows in January:
Haverford (Phildelphia): 41/28
Grinnell (Des Moines): 30/13
Carleton (Minneapolis): 22/6
I can’t emphasize enough how cold Carleton is! Wonderful school (as are the other two), but brutal winters.