<p>This also depends on how advanced the student is and what, if any, field of math is of greatest interest. Also, look at the number of students in the field, the availability of graduate courses and the double major options. Among the Ivies,historically, Princeton is the best known for math, particularly theory. Among the LACs, Harvey Mudd, St. Olaf’s, and Carleton come to mind. But there are a lot of great schools for math outside of this - obviously, MIT, Stanford, CMU, UChicago and CalTech.</p>