Physical education (or PE) was a course of study related to exercise.
Mr Okehurst was the PE teacher at Coal Hill School in March and April 1963. Susan Foreman attended his Tuesday and Thursday classes. (PROSE: Time and Relative)
One of the rooms on the Minotaur's prison ship contained what appeared to be a cross PE teacher. (TV: The God Complex) Rory mentioned having had a sadistic PE teacher. (TV: The Doctor's Wife)
The Twelfth Doctor mocked Danny Pink about being a PE teacher, instead of a math teacher, because of his past in the army. (TV: Listen onwards)