Mathematics.

[scrumpleberry]

I wish I was good at math, but I'm dire at it, unfortunately.

Fortunately, I never have to take a math class again, I'm pretty certain, and it's not at all needed to teach English, so~

Because English teachers never have to worry about calculating their students' grades :rolleyes2





...because they have computer software to keep track of grades now

Calculating percentages is easy, if you train yourself to do it it should become automatic.