Harry's Coming of Age

[Alice I]

Yeah I'm July 7th so I was always the youngest in my class as well.
The test may not be a requirement in other states.
NY is the exception to so many rules
Our taxes are too high as well.
BTW is it true that you do not pay income tax where you live Athena?
I'm movin' if that is the case!!
NY has some of the highest income tax in the country, and Irondequoit where I live does have the highest property tax!

[Nobby]

Well since Jk is British im guessing she based it on the british school year! ok the school ages start from September the first till August the 31tst. So hermoine whould be one of the oldest in her year, making harry one of the youngest!!! he must be one of the youngest cos he turns 11 in book 1- just before he starts Hogwarts (or secondary school in Engalnd). 11 is the minium age. he couldn't be one of the oldest because the other students would be too young for secondary school

[Athena Appleton]

Some folks are determined that eleven means eleven and that Hermione had to have started Hogwarts at that age because that's the rule. That would mean that she turned twelve three weeks after starting Hogwarts and that she is almost a year older than Harry and Ron. There is no conclusive proof in the canon of which year Hermione was born, although she and Harry are referred to by Dumbledore as being "two thirteen-year-old wizards" in PA, which would indicate a 1980 birth year. The characterization of Hermione seems to suggest that she's bit younger, too. However, we just don't know for sure at this point. In lieu of anything more specific, we go with what we do find in the books, which is that Hermione was thirteen toward the end of the 1993-1994 school year, and therefore was born in 1980.
It is worth pointing out that Hogwarts doesn't necessarily follow what current British schools do, since 1) it was founded long before the current British school system was established, 2) it is really located in Scotland, which has different rules, and 3) it's part of the Wizarding World, which doesn't follow British rules on things anyway.

This is taken from the one and only Rowling-approved timeline of Hermione's life at the HP Lexicon. According to them, Hermione entered Hogwarts when she was ten years old, and three weeks after classes started, she turned 11. This makes her two months younger than Harry, not ten months older. And it explains a bit about the Hogwarts system vs. British system.

[Athena Appleton]

oh yeah... this also, by the way, contradicts what Rowling herself said about witches and wizards receiving their acceptance letter on their eleventh birthday... maybe they made an exception with Hermione's. But, I'm pretty sure that the Lexicon's timeline has been approved by Rowling.