I don't get what you mean about the third panel? why would the teacher not be annoyed already in the third panel
No, logically speaking, he should be annoyed. I just mean for a visual contrast. You can have this entire joke; the thing can be done with just word balloons and it wouldn't change anything. I'm just saying that changing the expression would make a little visual joke as well, instead of getting the
completely static image of the zebra that we get here.
I mean, look at him. I know they're hand-drawn at this stage, but that Zebra is practically copy-pasted; the
exact same between the two panels. Again, a visual medium no-no unless you're using it for something.