To me the images have been shot with tilt/swing function employed in a high-end lens (or 5x4 + 6x6), certainly not the vague, imprecise LensBaby optics.
It's a very specialised skill; I suspect he's spent a lot of time refining his technique to work at speed when and where required (kids that age aren't going to remain still for long!). In some examples the tilt (or swing) of the lens can be discerned as a peg, but there are also some peripheral irregularities i.e. symmetrical lines of delineation are not where they are expected... possibly post-image print tweaking (that doesn't mean Photochop).