Advice for course homepage design [on hold]

I would love some input on the UX of the website that I've been designing.

The webpage can be found at https://www.math180.coursehome.page/ -- it's purpose is to serve as the homepage for a mathematics course (not specifically calculus; this is just a placeholder course).

In particular, I am anticipating that a large portion of the users will be mobile users.

Any input and criticism (typography, navigation, etc) is appreciated!