Mr. Henning is a science teacher at Ridgeway Junior High School.
Mr. Henning has been at Ridgeway for 30 years. He is Carly, Sam, and Freddie's science teacher and was also Spencer's. Spencer described him as "such a loser" who "smelled like rotting wood."
He makes his first appearance in iGo Nuclear setting the class a project. On Project day, he gives Sam an A and gives Freddie a D- (making him go on the Root and Berry retreat). At the end, he gives Carly an A+ (first student ever), but finds out she built an illegal nuclear generator and gives Carly the chance to earn extra credit by taking himself, Carly, Freddie, Gibby and some other students on the Root and Berry Retreat. He is very odd, Sam's project was rubbish (she put in no work, did no research, and talked about how an orange she got for lunch is recyclable) and Freddie had a very good project (he even imported worms from Portugal), but found Sam's project good and Freddie's project rubbish. This proves that he often doesn't make the best choices, except for when he gave Carly a second chance to do her science project, although she failed it when it turned out she used stolen nuclear energy, resulting in both her and Freddie going to Root-And-Berry.
He is not seen throughout the rest of the series, but is mentioned by Carly in iBeat the Heat as assigning the class to make a model of a utopian society.
- At the end of iGo Nuclear, Gibby can be seen on the retreat (for unknown reasons, presumably he failed his project).
- He doesn't have a toilet (He uses a backyard and a shovel instead).
- He eats peppers (especially the yellow ones).
- Presumed to like oranges.
- Spencer mentioned to Mr. Henning that he had "loser" for a science teacher; he was a "weirdo" and "smelled like rotting wood." Unfortunately for Spencer, Mr. Henning revealed that was him.
- He is single. (According to Sam.)