I was unable to find footage specifically on the proposed Social Security changes and youth.
To broaden your scope, you may wish to seek out the documentary "Eating Welfare" which is about Asian youth in New York City (Contact CAAAV:Organizing Asian Communities, more information here - http://www.alternet.org/wiretap/13462).
There is a call for a documentary from a group that is in favour of the changes to Social Security, "There is no Crisis: Protecting the integrity of Social Security" ("America's Most Realistic Home Videos" http://www.thereisnocrisis.com/node/2692)
MTV's Rock the Vote partnered with the AARP during the election in 2004, archives of the ad campaign are avaialble under 'Media' http://www.rockthevote.com/socialsecurity/index.php
Need more sources? A good resource to search is Media Rights - http://www.mediarights.org