What does the woman mean?

M: How did you like the new exhibit at the art gallery?
W: I still haven’ t been able to take any time out from studying.

M: Good morning. Mary, how’ s it going?
W: Pretty good, Bill. How about you?
M: Oh. I’m OK. How is that English class you’re teaching?
W: It’s going really well. I have a great class this year, I’ ve got 30 students.
M: That’ s good. I love to teach English. I’ m only teaching history now.