One joke for toastmasters is about the Buddhist monk who gets a pizza from a Zen restaurant. When he asks for his change after paying, the clerk replies, "Change must come from within."
Jokes for toastmasters should come throughout the speech. Quite often a joke at the beginning of a speech warms the audience up.
One example is suitable for a college speech. The joke starts with the premise that an engineering, physics and mathematics student have $150 to discover the height of a hotel. The math student uses the money to buy a protractor, plumb line, measuring tape and scratch pad. She uses the implements and trigonometry to discover the height of the building.
The physics student uses the money for stop watches, ball bearings and a calculator. He uses physics to solve the problem. The math and physics students see a hungover engineering student the following morning. The engineering student admits that he asked the bellhop how tall the building was before spending the money at the hotel bar.
A joke suitable for parents starts with the set up of a father indulging his toddler daughter as she brings him cups of water with her new tea set. When the mother returns home, she observes that the only water the girl can reach is in the toilet.