bigzarelli: Funny, I didn't think there were any rules in photography...
There is only one rule in photography. You have to have light to make a photo. All the rest are suggestions. IMHO.
CNY_AP: The shots of the first two kids look good to me - very natual framing to leave more space on the side they are looking towards. The boy's image on the bottom looks good too - by including more of the riding toy.I dislike the shot with the woman at the fence. I would have put her on the left side looking across the frame, and used the fence as the left border. Seems odd to have the subject looking off the frame, or about to walk out of the image.Does the rule of thirds apply to sports? The horses/polo shot has one horse cut off, and yet the main subject is nearly centered anyhow...i don't care for this image at all. PS: Not sure that others have said, purposely did not read other comments before mine.
I agree about the image of the woman at the fence. By having her looking at the edge of the frame it takes the viewer out of the frame.