When did Harry Potter first attend Hogworts?

Answer 1

I think the first time he sees Grindlewald is when he is in Dolores Umbridge's office in "The Muggleborn Registration Commission" chapter (Chapter 13) of Harry Potter and the Deathly Hallows.

In Umbridge's office, he finds a copy of Rita Skeeter's book, The Life and Lies of Albus Dumbledore, and in it he finds a "full-page photograph of two teenage boys, both laughing immoderately with their arms around each other's shoulders. Dumbledore, now with elbow-length hair, had grown a tiny wispy beard that recalled the one on Krum's chin that had so annoyed Ron. The boy who roared in silent amusement beside Dumbledore had a gleeful, wild look about him. His golden hair fell in curls to his shoulders. Harry wondered whether it was a young Doge, but before he could check the caption, the door of the office opened," (USA Scholastic hardcover edition, p253).

The next time he sees Grindlewald is in the very next chapter (Chapter 14, "The Thief") yet, incredibly, Harry can't manage to put two and two together. In the next chapter, he has one of those visions where he sees what Voldemort is seeing: "And now Harry was hurrying along a dark corridor in stout little Gregorovitch's wake as he held the lantern aloft: Gregorovitch burst into the room at the end of the passage and his lantern illuminated what looked like a workshop; wood shavings and gold gleamed in the swinging pool of light, and there on the window ledge sat perched, like a giant bird, a young man with golden hair. In the split second that the lantern's light illuminated him, Harry saw the delight upon his handsome face, then the intruder shot a Stunning Spell from his wand and jumped neatly backward out the window with a crow of laughter," (pp279 - 280).

The second time he sees Grindlewald is literally 26 pages after the first time he sees him. So, either there is a continuity problem here, or our hero has some serious short-term memory problems.

Answer 2

Harry Potter first attended Hogwarts when he was eleven years of age. At the age of eleven, Harry was picked up by Hagrid, who brought him in to the magic world to purchase his school supplies. Harry started Hogwarts at the same age as any other magical student, and stayed in for the entire seven year term.