FWIW, my DS would have had a list that looked just like your DS's when he was in K if it hadn't been a good fit. Teacher fit makes a huge difference, and they often think they are doing a great job (which I'm sure they are, just not for your kid's differences) and its all your kid. Which - it is. But that doesn't mean its ADHD or any other 'disorder.' They want a label that they understand and know what to do with (which is pretty normal).
You said he didn't do well in Taekwondo, but did fine in Lego and art classes. So he did ok in some classes where teacher fit and expectation were more flexible (yes?). And if you'd asked him, would he have told you he loved Lego and art, but only liked Taekwondo? Just guessing here, but sometimes fit is about preferred activities...
For my DS we looked at sensory processing issues and even did a year of OT (which he loved, b/c who wouldn't love an OT gym?). However the more I've learned the more convinced I am that its largely psychomotor OE for us as well. Combined with his other OEs, it can be a bit much at times. But no one thinks ADHD for us, and yet I feel I could've written your initial post. All this is simply to say - sounds like you know your kiddo well, go with your gut! That said, an eval isn't a bad idea -- it has helped us immensely to have the IQ numbers in advocating for appropriate school work!
