Where do I start first? Love the action of the boy. Foot up, yelling and that shirt is great. Not too bright for the other colors, and it reflects well in the water. And the texture changes, from rough rock to pebble-like rocks to water reflection. Well done.
I completely agree with Hazel's comments. With the fanciful colors in the pebbles it looks magical and the little boy is starring in his own game. The dark blues of the foreground and bkgd are a lovely backdrop for the brighter colors of the boy and rocks.