Online Summer Classes

Hey so this may not be the best place for this thread, but so be it.

I’m a current freshman at a 4 year university looking to take classes over the summer. However summer session at my school is really expensive, and all the schools where I live are quarter system whereas my school is on a semester system so the credits wouldn’t transfer very well.

Does anyone know of any schools that offer online courses over the summer that I can take for credit? Specifically I want to take Linear Algebra.

BYU Independent Study gets mentioned a lot, though I personally have never tried it. Penn State’s World Campus is highly rated, but costs significantly more.