This paper (1) presents a conceptual framework for analyzing the mathematics addressed in probability lessons and (2) uses the framework to compare the mathematics that two teachers with contrasting teaching approaches addressed in class when teaching the topic of probability. One teaching approach aimed to develop understanding; the other emphasized mechanistic answer finding. Class work on 193 problems was analyzed qualitatively and quantitatively, showing some similarities and some differences in the mathematics that the two teachers offered to students. The differences found seemed to be linked to the teachers' teaching approaches. The findings suggest that teachers who adopt different teaching approaches, to some extent, make available to learn different mathematics even when they use the same textbooks.