Poetry in Flox class

In our class (Flox class) we have been writing poems and this is one of them.

Boom, Crash! 
The shivering wave is like a shinning star 
Flying away in the light blue air. 
The wave is splashy like a penguin 
Flapping it's wing in the wave.

Wow! 
The wave is curved like a birds curved head. 
Splash!
What causes the waves to go up?