I can feel the sand on the feet, hear the giggles and the sound of the waves...I'd say that's a successful shot! Maybe would like to see a few faces a little more clearly, but this shot is not so much about the individual child as much as it is about the whole experience and the group. That's comes across quite well!
This is definately a wonderful candid/emotive image here.....
I especially love the sense of freedom that you have managed to capture here..... A dream capture of fun.
It shows perfect movement, and also perfect balance in composition.
What a happy photo. It makes me feel good to look at it. Wonderful photography! I love the black and white. It adds more emotional impact for some reason :)