Usage: "Phy Ed"

I'm editing a future story for Katherine Day, and something turned up -- very possibly a regional issue -- that I figured people here might be able to answer.

One of the supporting characters is a gym teacher. Katherine's protagonist uses the term "Phy Ed" teacher to describe him. I've only heard "Phys Ed" and "P.E". Dictionary.com considers the first and third of these to be abbreviations and calls the second "informal" speech.

I live just outside of San Francisco (where I was born and grew up) and Katherine AFAIK is in Wisconsin. This story takes place on the Atlantic coast, with New York the nearest major city. The time period is the present. Can anyone tell me which term, if any, would be used there?

Eric