CRDTs are relatively new so there may not be many classes yet that teach them. If you want to learn about them, I recommend you first watch this video: https://www.youtube.com/watch?v=OOlnp2bZVRs&list=WL&index=56... and then read this paper: https://pages.lip6.fr/Marc.Shapiro/papers/RR-7687.pdf . The video explains a lot of the math in a very easy to digest way and will make the paper much easier to understand.
