This premiered on HBO on March 25th.
Here's HBO's description:

Autism: The Musical
Rated TV14: ADULT LANGUAGE
Running Time: 94 minutes
Genre: Documentary
Inspired by her work with her own autistic son, Elaine Hall decided to create a musical theater program that allows autistic children to express themselves creatively and interact socially. The result was the Miracle Project. Countering the bleak statistics regarding autism (one out of 150 children are diagnosed in the U.S.), the California woman pledged to lead a group of autistic kids in defying expectations by writing, rehearsing and performing their own full-length musical. This film follows five Los Angeles children and their families over the course of six months and observes how this musical production gives these young performers a comfort zone in which they can explore their creative sides. (TV14)


Watch it online here: http://www.hbo.com/docs/programs/autism/video/
Other showings on HBO: http://www.hbo.com/apps/schedule/ScheduleServlet?ACTION_DETAIL=DETAIL&FOCUS_ID=647488
You can learn more and order the DVD here:
http://www.autismthemusical.com/index.php?session=myhomepage&id=