There is a lot to respond to here, and I wish I didn't have to do it on a phone.
I'm starting to think that it is just one of those devolpmental stalls. But I will keep my eye on it. We are testing next month, and I believe I've read at some point that a certain discrepancy will point to any vision issues.
There is definitely a component of manipulating the protractor which makes it difficult. Then there is the issue of struggling to see which angle in a figure we are talking about. For example, if the is an image of a cube, he is very confused about what angle we are trying to measure. Any image with multiple angles and not simply two lines, is hard to grasp. Non-Parallel lines that cross far off the page are hard for him to visualize. The first section of Beast Academy 4a was very difficult for him, and I felt I had to walk him through all the problems. Right now hitting Singapore's Geo section, it was much easier, but not as smooth as I'd expect, especially after recently doing Beast. I guess sometimes you get concerned when things run so effortlessly for too long, and then, they don't!
As for vision, I tested him by having him build some 3d block puzzles that we just got. First try was what had me worried. But after getting used to the game, by second day, he had no issues building patterns.
Thanks for all your insights. Will continue to watch for vision, but next time, I will try to remember that developmental stalls happen with these minds, just not frequently enough to habituate me to them!
