An old teacher I once had called it "Autosomething's in focus". Quite appropriately, if you ask me, because SOMETHING is always in focus, but what you WANT in focus, that's another story. Make sure you're looking through the eyepiece viewfinder, not at the screen on your camera when taking pictures, so what you want is in focus. (In the second photo, the girls dress is in focus more than her face, but the composition is great).
I agree that the lighting is a little harsh in the first one, and that's just a result of direct flash. (Of which I am the world's biggest non-fan)
I my opinion, your composition is great, you just need to start working with the settings on your camera to make the images look the way they do in real life. If you're not using an SLR, check to see if you have ISO, shutter speed, or aperture settings on your camera, and start playing around! Have some fun, cuz those kids sure are!