Excerpt from Birmingham:
SCLC organizers started to plan "D Day."
Unlike the other demonstrations, all of the D Day demonstrators would be children. James Bevel explained why the SCLC turned to children as demonstrators:Most adults have bills to pay -- house notes, rents, car notes, utility bills -- but the young people . . . are not hooked with all those responsibilities. A boy from high school has the same effect in terms of being in jail, in terms of putting pressure on the city, as his father, and yet there's no economic threat to the family, because the father is still on the job."
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On May 2, children, ranging in age from six to eighteen, gathered in Kelly Ingram Park, across the street from Sixteenth Street Baptist Church. Around 1:00, fifty teenagers left the church and headed for downtown, singing "We Shall Overcome." They were arrested and placed in police vans. Another group left the church, and they were also put in vans. Another group left, and another. Soon the police began stuffing the protesters in school buses because there were no more vans. Three hours later, there were 959 children in jail. The jails were absolutely packed.
The next day, over a thousand more children stayed out of school and went to Kelly Ingram Park. Bull Connor was determined not to let them get downtown, but he had no space left in his jails. He brought firefighters out and ordered them to turn hoses on the children. Most ran away, but one group refused to budge. The firefighters turned even more powerful hoses on them, hoses that shot streams of water strong enough to break bones. The force of the water rolled the protesters down the street. In addition, Connor had mobilized K-9 forces, who attacked protesters trying to enter the church. Pictures of the confrontation between the children and the police shocked the nation. The entire country was watching Birmingham.
The demonstrations escalated. Because the jails were filled, the police did not know what to do. Finally, the Birmingham business community, fearing damage to downtown stores, agreed to integrate lunch counters and hire more blacks, over the objections of city officials. King had gotten his much-needed victory.
http://www.watson.org/~lisa/blackhistory/civilrights-55-65/birming.html