I seem to fall into both categories. I started kindergarten at age 4 and went three years; my mother used a private kindergarten as a kind of daycare. I starte

I seem to fall into both categories. I started kindergarten at age 4 and went three years; my mother used a private kindergarten as a kind of daycare. I started first grade at age 7. I learned to read in first grade almost instantly and was reading children's novels, not picture books, in just a few months. My brother, by contrast, who followed the same academic path, taught himself to read around age 4 by looking at comic books that I was buying. (This was all in the early '60s.) Academically I did so-so. Less of a problem with ability than boredom. I got into a good college solely on my standardized test scores. In college I had a B average. One advantage that I remember from being a year older than my classmates was that I was considerably larger. I was large for my age, and a year older to boot. Despite being bookish and a nerd, before that was considered a good thing, no one would mess with me. Plus I went to kindergarten with, and was friends with kids that were up to two years older. A lot of that faded away as we all got older and the differences evened out. But the main advantage, in retrospect is that I always considered my self an outlier. I didn't need peer support to be interested in things and didn't really care much about what everyone around me was doing. I expected to do the unexpected. I got into computers and computer graphics in the late '70s when no one had even heard of such a thing. I was playing with the internet long before it became a thing, or was even very useful. I started my own business a year out of school was doing entrepreneur type things until I hit forty. (A downside is that I would often get bored with something _before_ it became a thing, and would have moved on to the new shiny before something got viable.) These days I'm involved in education, university level and adult education, and it's interesting to see the mix in student's ages at the other end of the education cycle. Older students, especially those that have been out of school for a while, are much more motivated and serious about their subjects. I suspect there is quite a bit of selection bias here, as those not serious aren't likely to try and get more education. But I also see some younger students who are delighted to suddenly be in a place where they can take their education seriously and stretch their abilities.