He's looking unusually pensive, probably because standing in line for a sled forces you to stand still, at least momentarily. Standing still is NOT Boy Wonder's natural state. Generally speaking, he is a running, jumping, flying Legos around the room, hula-hooping, wrestling the dog to the ground kind of kid. I'm pretty sure he's thinking, "Ten more seconds until I explode. Ten more seconds until I . . . nine. NINE more seconds until I explode. . . . "
But maybe it's, "This orange sled is going to be a whole lot better than a cookie tray. A WHOLE lot better than a garbage can lid. I love orange. No matter what my Mom says."
Or maybe it's, "Did I forget to put underwear on again? AGAIN? What will people think? Hmph. Who cares. No one can see it anyway."