People thought that this was the same character from Happy Days (1974), since both were named Charles, both played by Scott Baio. (And Charles' last name in never revealed in CIC). But Happy Days took place from the 1950s to the 1980s, and there's no way the Chachi Arcola character would still be 18 from the early 1960s, which is when Happy Days supposedly ended, to the mid 1980s which is when Charles in Charge started. The only plausible workaround for that fan theory could be if this Charles (in charge) was aka Chachi Arcola Junior.
... You're grounded for three months. No TV, no stereo, no allowance, no phone. Your life is school, homework, eating, sleeping, and chores - *lots* of chores. And if you have any free time, I suggest you spend it dwelling on why you were grounded.
Stan Pembroke: ....