How many instances in the show can you remember where the fourth wall
is broken? It doesn't count if it's part of a performance in-show (like B-TV, a story being told by someone, KYDS radio, the Imagination Station, etc.) -- just a regular, real 'day in the life'.
Off the top of my head, there's two I can think of:
1) In "Two Sides to Every Story" Jimmy says, "I'd tell you the rest, dad, but this is a family show".
2) All of "Dr. Dobson Comes to Town", although I understand that episode is ambiguously canon.