> 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.

This. The grade one is assigned to is a system carried over from the 1800s and does not reflect what we know of child and brain development today, or critical social and physical development needs to realize every child's potential.