Agree about the composition. If you're going to have empty space in an image, behind the subject is not generally the best place. I think #1 would be much stronger if you were to crop away just about everything to the right of his back. I like #2 in terms of the concept; I wish you'd turned his body a bit more toward the camera, and watch the details. The little wisp of hair protruding under his wedge is NOT ideal. Like #1, #3 could stand to lose the whole right side of the image. You've also lost some detail in the vest, but that should be recoverable with the blacks & shadows sliders in LR. The 'off-camera gaze' of #4 is really more of a fashion pose, I'm not sure that I'd use it in a situation like this, but I guess it gives him an 'air of mystery' that kids his age like. Don't forget to remind them clients at the pre-shoot consult about the importance of ironing clothes!
Just my $00.02 worth - YMMV
~John