‘Mary Poppins,’ designed for autistic kids

>>> here in new york this past weekend it was not just another broadway matinee. sunday's performance of " mary poppins " was specially staged for the benefit of young people with autism and their families. part of an effort of a nonprofit group making a difference. our report from nbc's anne thompson .

>> reporter: it's curtain time at " mary poppins ".

>> in 2:45 time you will without question have changed the lives of a whole group of people who are out there this afternoon.

>> this is a performance for children with autism and their families.

>> reporter: to make this event possible, the associate director changed the show.

>> how many times in your show are you having to adjust the set?

>> a lots. majorly. i would say in every scene.

>> reporter: more than 40 audio and 200 visual cues were toned down which can disturb people with autism. the musical director went through every song.

>> we spent time identifying where pitches of voices may simply get too high.

>> reporter: they cut one musical number giving burt just seconds instead of five minutes to travel four stories from the stage to the ceiling.

>> while the kids are watching the show go on, i'm in the elevator undressing and putting new clothes on in under a minute.

>> reporter: the challenge is so make these changes and preserve the magic of the musical. this is a boisterous audience. moving, shouting, just being themselves. exactly what families need seautism speaks founders bob and suzanne wright.

>> all the judgment's gone, there's nobody judginging them.

>> to have these families have a day of total normalness is a wonderful thing.

>> an idea theater groups across the country may try out.

>> we put this one out overnight. guess what, guys, there's an audience here, there's a market here.

>> reporter: one look at these faces tells you, the magic is