Q: What’s the best season for jumping on a trampoline?
A: Spring time!
Explanation: The northern hemisphere is about a third of the way through the season of spring. Of course summer will come after spring, and then fall and winter. Spring is a beautiful time of year as the trees bud and bloom, the flowers are reborn, and the days get longer. (Actually, days do not really get longer than 24 hours, but the amount of sunlight during the day increases.)
A trampoline is a piece of equipment that has a strong fabric attached to a frame with springs; the springs make you bounce up and down. Springs are coils of wire that can get longer when stretched, and then pull back into its original form. You might find a spring used to close a screen door, to make the tip of a pen come out or go in, or to make a mattress more comfortable.
This joke is funny because it plays with the word spring: A season of the year and a coiled piece of metal. Springtime is different from spring time, too. If you play on a trampoline, you will enjoy your time bouncing because of the springs.
Here are some amazing trampoline athletes (thanks to the springs):