USC freshman Jacqueline Martinez can still smell the stale popcorn and sticky soda-stained floors, a lingering reminder of her tough childhood. When she was only 11, she began accompanying her parents to their job cleaning a movie theater. They would leave their South Los Angeles home at 1 a.m. for the graveyard shift. As Martinez got older, she pitched in, sweeping screening rooms and scrubbing hot dog and popcorn machines. It was exhausting.