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Excerpt from a 2011 Insider Higher Education article (bold text added by me):

In an effort that some are calling the first program of its kind, Georgetown College, a Christian liberal arts college in Georgetown, Ky., is hoping the same high interest in foreign languages in K-12 schools can be translated to the postsecondary level. This fall, the 1,300-undergraduate college will welcome its first cohort of 15 students to its Inmersión en Español program. These students still will be able to pursue a major in any of the college's departments, but they will take about one-third of their core requirements in Spanish instead of English. Specifically, five of the courses that are part of Georgetown's Foundations and Core Program will be offered in Spanish. They will include, at first, required courses in critical thinking, literature, philosophy, political science and mathematics. The courses will be taught, in large part, by professors who are versed in both Spanish and the core discipline. For example, the college recently hired a Ph.D. in Spanish who has a master's degree in philosophy.

The article continues:

...the initiative at Georgetown is thought to be unique, said Emily Spinelli, executive director of the American Association of Teachers of Spanish and Portuguese. “Although there might be other colleges or universities that offer required general education courses in Spanish, I am not personally aware of them,” she wrote in an e-mail.

I altered the link to the program above to direct you specifically to the course offerings.

Philosophy is already listed, and under "Upcoming Courses" you will also see:

Other courses planned include: Political Science, Biology, and Math.

The comments from the Inside Higher Education article also mention a former school, Elbert Covell College (ECC), at the University of the Pacific.

Though ECC has since closed, it once had the sort of offering you describe.

A school description can be found here, where the relevant section begins:

Elbert Covell College, a liberal arts and sciences college also, was unique because all courses were taught in Spanish.

Finally, an October of 1963 article in Time Magazine remarks: