This is actually reflected in his most famous work, "Diary of a Wimpy Kid", where the protagonist Greg Heffley is also a mediocre student who often gets into trouble.
While Kinney might not have excelled academically, his creativity and storytelling skills were evident from a young age. He developed his writing and drawing talent outside of the traditional classroom setting, ultimately leading to the success of his "Diary of a Wimpy Kid" series.