On Saturday thousands of students are expected to take to the streets in Washington and cities around the country for the March for Our Lives rally. Organized by Florida school shooting survivors, they are demanding an end to school shootings and other gun violence. CBS News embedded with the Parkland students as they formed the Never Again movement. Watch the CBS News documentary, "39 Days," which airs Saturday, March 24, 2018 at 8 p.m. ET/PT on CBS.
