Susan, it’s a pretty good shot as you have cropped already. Editing is a personal choice. I think that there are a number of elements to this picture. Cropping one thing or another would change the image. This is something to think about as you press the shutter. Take a couple more shots, horizontal, vertical, zoom in, zoom out. That way you have options in the edit and crop of post production. Sometimes the best shot is not seen in the viewfinder at that moment. It’s easier with digital. I tend to go with tighter cropping and more zoomed in detail. But it’s hard to make any general rule. I like this shot. The elements in play are the kids. Do you emphasize them more? If you do, you lose the beach and the houses. Are the houses in the background important to the image or the story? The reflection of the kids’ legs adds another interest. Keep them or not, it’s your decision as photographer. Considering the image it looks as though it doesn’t need anything more and subtraction would not help. Oh! And you were in the water when you shot this! Good for you!