Dennis Denard is a minor character in Diary of a Wimpy Kid: Hard Luck who sells old science projects in the school's storage room. The storage room apparently has no door, so Erick Glick has to make a secret knock a few feet away so that the school staff doesn't notice. He was later caught with all other students after somebody exposed them. He had been held back from eighth grade twice and was later sent to detention for a year and possibly summer school.
- Diary of a Wimpy Kid: Hard Luck (First and only appearance)