Wether or not you find the pranks pulled by Sideswipe, Sunstreaker, Bluestreak, and Barricade while Elita and Optimus are on vacation, Prowl's encouragement of them is funny in it's own way.
The explanation for Bumblebee's colors, specifically his and Ironhide's reaction to a home movie of the incident being pulled up.
The youngsters mentioned above paint bomb one of Ironhide's trainee classes.
Ratchet's reaction to the above incidents: socking his elder kid in the eye and knocking him flat on his back until he adequately explains why he's encouraging the shenanigans (which are causing a spate of minor injuries). Said "kid" is a highly trained martial artist.