ADHD?

I went with Henry's class on a field trip recently, and seeing Henry with his peers really highlighted for me how INSANELY short his attention span is. I mean, I knew it was short, but I chalked a lot of it up to "he's a boy" and "he's just learning to hear properly so he's probably being overstimulated" and that sort of thing. Really, those ideas are probably true. And maybe he'll grow out of it. Maybe. I'm not so sure now. He's too young to know for certain, but I'm keeping the possibility of attention disorders in the back of my mind.