I like the hyper-saturated look of this image; it fills the background with the energy of a small child, making the scene almost fantasy-like. This should have scored much higher.
I scored this one a "4" during the challenge. The colors are off, which is the first thing people seem to be noticing. The little girl also seems a little out of focus to me, which is probably from the slow shutter speed. I would think on an outside shot, you should be able to work with a little higher shutter...at least a 1/60 would probably have made a difference here.
You might also consider cropping some off of the top, as I think it would bring the viewer's attention more to the subject. Hope this is helpful!
This is a great unique expression, the only problem is the colors being oversaturated, or maybe too much contrast, it is making the colors do strange things, if that is fixed, i could see this scoring 5.5+ pretty easily.