My daughter recently asked me, Why wasn't Professor Flitwick at the Sorting Ceremony?
I wanted to know why she had asked and she pointed out two things:
Professor Flitwick is not described as being present at the High Table right after Harry gets sorted (PG 122 HP and the SS paperback, 1999). I began to reply, but that doesn't mean he wasn't there and then she said,
"Flitwick is surprised when he finds Harry's name on his roster."
Professor Flitwick, the Charms teacher was a tiny little wizard who had to stand on a pile of books to see over his desk. At the start of their first class he took the roll call, and when he reached Harry's name he gave an excited squeak and toppled out of sight.
(HPSS pg.133 paperback, 1999).
Obviously, and reasonably, my daughter is concluding that if he had been at the sorting ceremony, he would not have been surprised at Harry's presence. Honestly, as a former teacher myself, I think he should have known ahead anyway - must've been fairly out of touch with the other teachers to not have had an inkling there was at least a possibility.
I understand this is sort of an inconsequential point in the book so it is likely there isn't an answer that is "in universe" and "in cannon." But I am trying to teach her to be a thoughtful reader and I felt it was an astute observation for a six year old and didn't want to just poo poo it. So, just in case there is something in an interview out there, I thought I'd ask - you guys seem to be able to answer it all.
My Daughter has decided to write directly to Rowling and ask. This is really bugging her. She say's "even if he wasn't there, he still should've known." We'll see if there is a response or not and update if there is. I am trying to talk to her about other possible reasons he was startled by the name as well. No return letter - not even a form letter from Scholastic - yet.
Final update: We got the standard Scholastic response packet which didn't even attempt to add any response to her specific question about Flitwick (though she proudly has her letter "from Rowling herself" hanging on her bulletin board). Alice has decided to move past it and recognizes different people interpret different things differently at this point.