(Strip Number 4058, Original Publication Date, 2 September 1981)
Panel 1: We find ourselves watching the aftermath of Mike trying to explain to John how Mrs Hardacre has singled him out for especial castigation; as he leans on the armrest of his chair in the hopes of getting sympathy from at least one adult in his vicinity, his hopes are dashed. That's because John doesn't even look towards him and continues hiding from his family behind his paper as he says "So....your Grade 2 teacher is a tough one."
Panel 2: He then tells Mike that a little discipline will do him good; that's sort of true but it's mostly his and Elly's job to provide that instead of being the failtastic parents they are now.
Panel 3: He finishes off being a highly defective dad by stating that some day, he'll look back and realize that the strictest teachers are the best.
Panel 4: Mike walks away and thought-bubbles "Why do they always say 'some day' when I'm trying to live through NOW?"
Summary: I'll tell you why; John has forgotten what it is like to be a child. Since he also can't put himself in Elly's place to see why she feels why her brain is trying to atrophy and will go on to be incapable of seeing how corrosive his 'humor' is to Liz's fragile self-esteem, it's almost a blessing that he takes up model railroading; it saves his family from dealing with his lack of insight.
ETA: The latest banner is a reminder that Lynn doesn't want to get close enough to a cat to be able to draw one properly.