How do you know they didn’t learn math? And putting the actual learning aside– what about making the most out of every opportunity Hashem gives you? He might not care if you got 100s on all your tests, but maybe He does care about how you dealt with the situations He put you in (not to mention how your parents and mechanchim feel about the money and effort they are investing in you).
Also, if you continued your math classes, you would learn how mathematical principles are of utmost importance in all fields of investigative study–including earth science.