Who's teaching 4th period again?

In every single classroom in junior high there's a small blackboard right next to the door that has that class' schedule for the day broken down by period.  Often it's a mix between subject, teacher and lesson. Today I came to my 4th period class to see this on that blackboard.

Who?

Next to the 4 is the Kanji for "English" and next to that it says "JonJonJonJon".  Needless to say, we all shared a good laugh over it.