There's no 'almost a year' about it. There were kids in our class who were more than a year older than other kids. This was even worse when kids moved from other states, as each state (at the time, not sure if it's still this way) had its own rules about what age/cut-off was used to determine when a child started school. For instance, my wife and I both graduated the same year. However, I'm 11 months older than her, because the cut-off in the state she's from was different than the state I'm from. So she, at almost a year younger, started school a year earlier than I did. One of my best friends in school moved to my school at the end of grade school, from out of state. He was in our class because the cut-off in his home state was earlier than our state. He's two months older than I, and a full year and a month older than my wife. So that's three different people, with wildly different birthdates, all in the same class. And at the younger ages, especially kindergarten and first or second grade, even a couple of months makes a huge difference in mental capacity for a child.

I was kind of middle of the road, age-wise, in my class. My birth month is nearly two months after the cut-off date (at that time), so I had some kids a month or two older than I was, but most were at least a month or two younger, with quite a few who were 7+ months younger.

It also sucked when it came to extracurriculars in grade school, which actually led to me not being as involved in them as I wanted. They went by a different age parameter than the classroom did, so I was thrust in with kids a year ahead of me in school. So instead of being with my friends, I was with these strangers who were already friends, leaving me to be the outsider, and I was the youngest of them, so I wasn't quite as good at the stuff as they were. So I got to experience it from both sides, being the youngest and the oldest in different things. In academics, where I was one of the oldest of my peers, I exceled and was consistently in the top of the class. In sports (basketball and baseball), where I was partnered with kids more my own age, but generally at least a couple months older, I was typically one of the worst because my coordination and skills just weren't where theirs were. But in gym class, when we played basketball or baseball, I was a solid middle-of-the-road player, as would be expected of someone who was middle-of-the-road age-wise.