Temporal Mechanics 201 was a second-level temporal mechanics class at Starfleet Academy, dealing with more advanced material than Temporal Mechanics 101.
In the 2380s, Doctor Erin Macdonald taught Temporal Mechanics 101 and Temporal Mechanics 201. She introduced her spring 2385 class by joking that the cadets could toss their Temporal Mechanics 101 PADDs, and that some in the class, namely Dal R'El, already had some advanced time travel experience. (PRO: "Ouroboros, Part II")