Question...

When he's sitting still, not engrossed in something but say on a car journey, does he tap? Tap his finger or shake his leg, rhymically?

If there is a label in his clothing, esp one which touches his skin, does it annoy him? Does he often ask for tags around his neck to be cut out?

Does he seem just generally restless or is he often thought of as a fidgety kid?

If he's really interested in something (book, movie, video game, whatever), does he ever not actually hear you if you speak to him?