The trampoline is an object in The Sims 3: Ambitions and The Sims 2 for consoles. In Ambitions, it is not an Athletic skill object like treadmills and weight machines. Instead, it's a recreational object that increases the fun motive, as long as the Sim doesn't fall off. Falling off a trampoline will cause a negative moodlet and a drop in the Sim's fun motive. A very simple, and non-recolorable, black bat-like shape hangs underneath a trampoline.
Trampoline is a hidden skill in The Sims 3.