WOW what a lovely post to read! I am so happy to hear of a positive experience.
I hope that the move up to first grade helps him feel more at home, and I pray that he finds some mental/emotional peers to enjoy!
How is he navigating school, the whole bus routine, changing to different subjects, lunchroom, etc. Does he like the overall experience?

Keep us updated, I hope he adjusts easily to the new classroom!