Action Packed / Smarty Pants - S2-E4
Continuity mistake: In "Smarty Pants", when the academic game ends the score is Dimmesdale 100 and Snerd 99, but right when the game ends it zooms out on the game and both teams have 0 points.
Super Bike / A Mile in My Shoes - S2-E6
Continuity mistake: When Vicky breaks a dish and dumps garbage in the sink that Wanda (as Timmy) was using to wash dishes, and gives her a shovel, one shot later the garbage disappears.
Super Bike / A Mile in My Shoes - S2-E6
Continuity mistake: After dad takes off the cloth (or something) covering the homemade bike, one rusty pipe handlebar handle snaps off. A shot somewhere after that has the handlebar ends switched.
Totally Spaced Out / The Switch Glitch - S2-E8
Continuity mistake: When Timmy seals himself in his closet, he boards up the door, but the nails and holes don't match places.
Totally Spaced Out / The Switch Glitch - S2-E8
Continuity mistake: After Timmy encounters Wanda the etch-a-sketch bat (and current godparent of Little Vicky) and before he goes out of the closet, the boards, nails and holes disappear.
Mighty Mom and Dyno Dad / Knighty Knight - S2-E9
Continuity mistake: In the end scene of Mighty Mom and Dyno Dad (the fight scene), notice the sky is a night sky but later when they loose their powers, Timmy's mom says let's enjoy our nice lunch and it suddenly becomes midday.
Answer: It's a joke. One cannot list all forms of entertainment. The list would never end. The boys were trying to convey how superior they were to the others, by saying that they were too good for comedy.