Huck, trying to answer your questions was absolute torture!! You shouldn't make us suffer like that.
There is just no way that I can choose a boy and say with absolute certainty that he was the most beautiful 11/12 y/o from a film. There are just too many.
I managed to narrow it down considerably to a few that struck me as particularly beautiful. Pelle Hvenegaard and Antoine Hubert are two that came immediately to mind. Jake Thomas in A.I was about the right age and very cute. Mason Gamble in Rushmore (although that probably has more to do with his character than his actual physical appearance). Michael Angarano is too old to fit in your category in Almost Famous and I haven't seen him in Music of the Heart, otherwise I would include him also.
But since I must choose only one, I will say Regis Arpin in Je suis le seigneur du chateau. Here is the only half-decent picture of him I could find on the Internet. (I would be forever grateful if one of you could make a nice gallery of DVD caps from this amazing film!!!)
(You need to Login or Register to view media files and links)Now, to answer your question: Why? Difficult to explain, but I'll try. For me, the impact of seeing a boy in a film depends in almost equal parts to three elements: 1. acting ability of the boy, 2. the character the boy is playing and 3. physical appearance. Good acting can be judged a bit more objectively, but the other two characteristics are really just a matter of personal preferences. The right combination of these three elements is what leads to what I might call a "transcendental aesthetic experience"
Generally speaking, the boys I prefer in films are "intense" characters in one way or another. For example, I have a thing for boys that display a superior intellectual and emotional maturity, while still maintaining the innocence, fragility and beauty of boyhood. The character of "Thomas" in Je suis le seigneur du chateau is the perfect example of such a character. Director Régis Wargnier's extremely melodramatic style emphasizes that intensity.
I don't know if that makes any sense. It's always hard to try to rationalize what are for the most part semi-conscious feelings.