Interesting artifact, very much a reflection of its time. During those post-war years, juvenile delinquency grew as a national concern as a teenage sub-culture began to emerge. In urban areas, gang "rumbles" often made headlines as youths clashed with chains, fists, and sometimes, knives, as dramatized in this 30-minute short. These could be seen as "turf' wars or, at times, as racial clashes, but rarely—if I recall the LA area of this short correctly— was anyone killed. Note how the solution portrayed here can be described as a "liberal" one — that is, by appealing to youths' better instincts, instead of the more traditional reform school path.
However, gangs-- at least in the last 50 years-- have evolved from street-level "clubs" into criminal enterprises, trafficking in drugs, guns, and other illicit activities that are often connected with adult-level prison gangs like the Mexican Mafia or the Aryan Brotherhood. Unlike the 1950's, rivalries are now routinely settled with "drive-by" shootings, at the same time, the bodies pile up in poorer and minority neighborhoods. Younger kids can easily be recruited since gang membership offers both status and the prospect of a money-making future. Just as importantly, liberal solutions, as portrayed in the Davis short, offer little prospect of success, while only those programs addressing the deeper causes of poverty and racism hold much promise.
Nonetheless, this earnest little docu-drama presents an interesting contrast to such sensationalized youth films of the time as Rebel Without a Cause (1955) or The Blackboard Jungle (1955). I am curious, however, where the producers expected the 30-minutes to be shown and to what effect.