Today, I took my three youngest (8, 5 and almost 3) to a special Children's performance of Mozart's opera "The Magic Flute" in San Francisco; it was wonderful and the kids were transfixed. I'd wondered how my almost-3 guy would handle sitting for over an hour, but he was so enthralled with the sights and sounds that he sat on my lap the whole time, nearly without moving.
That was probably a great experience for them.