Trampolines can be found in many gardens and also in some playgrounds. They offer an easily
accessible vertical motion that includes free fall. In this work, the motion on a trampoline is
modelled by assuming a linear relation between force and deflection, giving harmonic oscillations
for small amplitudes. An expression for the cycle-time is obtained in terms of maximum normalized
force from the trampoline and the harmonic frequency. A simple expression is obtained for the ratio
between air-time and harmonic period, and the maximum g -factor. The results are compared to
experimental results, including accelerometer data showing 7 g during bounces on a small trampoline
in an amusement park play area. Similar results are obtained on a larger garden trampoline, and even
larger accelerations have been measured for gymnastic trampolines.