These are the known detentions Greg has got in the series. There is one from The Last Straw, there is one detention from The Third Wheel and one from Cabin Fever for defacing the school walls.
- 1st Detention: For sleeping in class.
- 2nd Detention: For defacing the school walls.
- 3rd Detention: For selling a fake card to a kid that was about a secret elevator (which was actually the janitor's room). He originally got it on his first day on middle school by an eighth-grader.
It's unknown if Greg got detention for having an excessive amount of toilet paper. This is unlikely, since Greg would have probably mentioned it, if so.