  Quantum revival is described as the time-periodic reconstruction of a wave
packet initially localized in space and time. This effect is expected in
finite-size systems which exhibits commensurable discrete spectrum such as the
infinite quantum well. Here, we report on the experimental observation of full
and fractional quantum revival for classical waves in a two dimensional cavity.
We consider flexural waves propagating in thin plates, as their quadratic
dispersion at low frequencies mimics the dispersion relation of quantum systems
governed by Schr\"{o}dinger equation. Time-dependent excitation and measurement
are performed at ultrasonic frequencies and reveal a periodic reconstruction of
the initial elastic wave packet.
