I too, think its a great idea. In fact, it isn't really a new idea, because in many parts of the world, this is a 'very' common practice.

I'm not sure if it would make a difference to very young children in elementry school, but once kids hit puberty, their eyes start wandering, and they start focusing more on 'that beautiful girl or that cute guy', instead of on their education. It would probably reduce the amount of teenage pregnancies and unwanted babies too. In fact, I would LOVE for this to happen before I have my own children, and they are ready to begin school.