Corrected entry: After Mr. Holland performs a concert for his son's school for the deaf, the audience bursts into applause. But deaf people do not clap in applause, they wave their hands (it is more visually energetic). Since most of the audience was deaf students and teachers, there really should have been a lot of waving, and only a few sparse clappers. But I'm sure that would have sounded awkward and anticlimactic for this very emotional scene. Given the research the filmmakers put into ASL, I'm sure they were aware of this, but opted for the clapping to suit the typical (hearing) movie-goer.
Phixius
11th Sep 2010
Correction: Deaf people are aware of what clapping is. Those in the audience know that Mr. Holland is not deaf and that applause would have a greater impact on him than waving. This was their choice, not a movie mistake.
Phixius ★