Opinion on Claremont Graduate U. versus Cal Poly Pomona?

My son has been accepted to Claremont Graduate University and Cal Poly Pomona for a master’s degree in Math. After completing the FAFSA and being advised of his financial aid awards, it seems Cal Poly will cost about $13,000 a year less. I believe Claremont is a more highly regarded school, but is it worth that much more money?

Any opinions would be much appreciated. Thanks!