Panel 1: Mike attracts John's attention by hollering about how much he hates stoopid math while attracting our attention by being a Peanuts character in the realish world.
Panel 2: This leads to the bog-standard "How not to teach OR learn anything" pas de dumbass that ensured that the Patterson children got shitty grades as John mansplains the Pythagorean theorem to a sullen goof son who won't explain the real problem: someone is making him do math without a calculator because she didn't have one growing up.
Panel 3: When he makes with the Peanuts crap and hollers "I know, I KNOW, I KNOW!!!!" at John, John mutters "Fine."
Panel 4: When John talks about how his ignoramus of a son thinks that he knows everything, Elly reminds him that that's why they're so hard to teach. Since she's not the one having to deal with their common failure to parent this time, she can be the one making witless banter.
Summary: As howtheduck will demonstrate over the next little while, Mike would rather not waste his time learning anything or paying attention in class because tomorrow, we see something far more to his tastes: enabling his entitled shlump of a friend as he makes a sinister and ridiculous ass of himself because he and Lynn have funny ideas about girls who wear 'dangerous' outfits.