How does Caracutus brush off his children skipping school?
"Oh, well, uh... gives the other children a chance to catch up!"
It's a little moment, but in the song "Chu-Chi Face" when Baron Bomburst and the suit of armour snap their fingers in frustration at the same time. Of course the suit of armour isn't animate, but the laws of reality can be broken for a good gag, right?
Fridge Horror: In addition to the above, another suit of armor obliges when Potts asks it to hold something; during the final battle, a suit of armor bops someone on the head with a mace, then raises its visor to reveal that someone is indeed wearing the armor. Does this mean that the Baron has his guards disguised as suits of armor?
The spies that try to be English with horribly out-of-date information as to how the locals really dressed and acted.
Not to mention their classically slapstick antics while trying to capture Caractacus and Chitty, including mistaking Grandpa Potts for the inventor — hilarious.
Truly repeatedly hitting Caracutus during their duet. Most of the times seem possibly like accidents, but the last one clearly happens on purpose.
The "Posh!" musical number; Grampa has just been abducted, little house and all, by Baron Bomburst's zeppelin, and at one point the balloon starts to drop, forcing the crew to toss various things in an attempt to lose weight.
Baron: We are still losing height!? But zhere must be zomething we can throw out!
Agent: But there's nothing we can throw out!
Other agent: Yes, there's nothing... (Chuckles nervously when he sees that he and his fellow agent are being stared at)