This week marks the 50th anniversary of that summer of 1964 when black and white volunteers from across the country went down to Mississippi to end rigid segregation and blocking voter registration among blacks.

The gripping story of those volunteers and how they changed the country is told in the AMERICAN EXPERIENCE documentary Freedom Summer. It airs tonight on GPB at 8 p.m.

Missed "Freedom Summer" when it aired on GPB? You can watch the entire documentary below until July 23, 2014 right here.

WYSIWYG: EMBEDDED VIDEO

If the description of the film doesn’t spark the interests of your summer school history students, perhaps showing them clips from the film will.

PBS Learning Media has curated clips from the film along with snippets from the documentary “Freedom Riders” which chronicled the brave black and white volunteers who broke segregation laws by riding Greyhound buses to the south together. Many of them were mobbed and beaten and their buses were firebombed.

One of the clips from "Freedom Summer" shows the seemingly unlikely catalyst of the campaign: a comedian. Dick Gregory, called media attention to voter registration reprisals in Mississippi. His sounding the alarm inspired the freedom summer campaign. You can watch it and download it now.

WYSIWYG: EMBEDDED VIDEO

Students can gain a more organic experience by visiting Atlanta's newly opened Center for Civil and Human Rights, a space that connects the American Civil Rights Movement to the Global Human Rights Movements.