He's advanced, but what does "advanced" really mean? That probably won't become obvious until later on. I had a child who was doing most of the things on your list at those ages, and people who watched her were "wowed" and noted that she seemed to be very advanced. In kindergarten she was still looking "advanced" - but she's dyslexic, and by the time she was in 2nd grade she was struggling to stay at grade level in school. She has areas of academic strengths, but they are not what I'd label genius-off-the-charts strengths, just strong strengths
My EG ds, otoh, wasn't doing any of that at the ages you've mentioned. He wasn't even talking at your ds' age - but once he *did* start talking, he was talking about ideas that were extremely novel, complicated, and deep - and he's my kid who's continued to stand out in terms of where he is intellectually compared to peers.
In any event, no matter *what* - follow your ds' lead - let him explore the things that interest him, enjoy him, have fun with him. I wish my children were still young (at times!) - it is so fun to discover the world with them when they are your ds' age
Best wishes,
polarbear
