I Am Sam

Rita: I just don't know what to call you: retarded, mentally retarded, mentally handicapped, mentally disabled, intellectually handicapped, intellectually disabled, developmentally disabled...
Sam: You can call me Sam.

I Am Sam is a 2001 American drama film written and directed by Jessie Nelson, starring Sean Penn, Dakota Fanning and Michelle Pfeiffer. It's about a mentally handicapped man who fights for the custody of his seven-year-old daughter.

For his role as Sam, Penn was nominated for the Academy Award for Best Actor.

Tropes used in I Am Sam include:

Children Raise You
Disabled Character, Disabled Actor: Sean Penn, of course, is not really developmentally disabled — but many of the actors who play his housemates are.
Dumb Is Good
Inspirationally Disadvantaged: Averted.
I Want My Beloved to Be Happy: Sam for his daughter.
Jukebox Musical: Sort of, as the soundtrack consists of cover versions of songs by The Beatles.
Man Child
Oscar Bait: As pointed out in Tropic Thunder, Sean Penn tried just a little too hard with this one, not to mention the creative staff behind the movie.
Realistic Diction Is Unrealistic: Averted entirely when it comes to Sam, who tends to repeat himself and mix his words. Interestingly, the more a character comes to like Sam, the more they talk like him.
- That they start talking like him when they come to like him can be explained by the fact that this happens in real life. If you spend a lot of time around people that talk a certain way, then you start acting and speaking like them. People who spend time in foreign countries develop a different accent or dialect, and people who spend time around someone who, say, says a certain word a lot or has a verbal tic will find themselves using the word or verbal tic.
Shout-Out: When asked what his daughter means to him, Sam makes a heartfelt speech that the judge points out is from Kramer vs. Kramer.
Tragic Dream: Sam wants to be a good father, but he just isn't capable of raising his daughter alone.