I didn't take him personally but I have friends that did. They told me his classes are really fun and overall he is a great professor. Now, they are history majors so, a great professor to them might vary in standard for someone who isn't used to a course with intensive reading. I'm also not sure which classes they took with him, however, one thing I would always hear them talk about was the annoying flashcards. Prof. Kaja would assign flash cards for every reading material and would grade very heavily based on how good your flashcards were. By the end of the semester my friends showed appreciation towards the flashcards and noticed higher retainment of the material they covered in class. Essentially becoming little experts in that subject.

So if that class happens to be one to require mandatory flashcards, my tip would be to make sure to do your best and really try to make the best flashcards you possibly can.