After Arnold and Dudley skip school for three days to avoid contact with the bullies stealing their lunches, and Willis and Kimberly discover what is happening, Arnold misspeaks, He says, "Those two guys came to my school again today." But at that point in time, Arnold was already skipping school to avoid confrontation with them.
Both Sal Lopez and Shannon Presby, who are said to be " older guys from high school" by Arnold, were well into their twenties when this episode was filmed.