The very first televised collegiate debate took place on Wednesday, April 3rd, 1940 between Columbia University and Bucknell University. It was titled “Resolved: That the Dust Bowl Situation Requires That the United States Take Extraordinary Measures for its Improvement,” according to a brief article in The New York Times announcing the broadcast. The same article stated that the debate would run for an hour; television listings show it airing from 8:30-9PM . It was carried live on NBC’s experimental New York City station W2XBS.
The debate took place at Radio City Music Hall in New York City (part of the Rockefeller Center). George Denny served as moderator. Each college had two participants: A. David Kagon and Charles Schneer for Columbia, John McKenna, Jr. and Raymond Underwood for Bucknell .
Bucknell’s position was that that government should “spend five billion dollars to rehabilitate the dust bowl” while Columbia felt that the dust bowl “was not even appraised at more than three quarters of a billion” and suggested that “the 85,000 trees planted since 1935 would do the trick and save the 600,000 square miles from dust decay” .
In its review of the debate, The New York Times noted that “a tele-debate is more interesting than a blind radio argument” because “it enlivens the debate with personalities” and gives viewers the “opportunity to look into the eyes to judge the sincerity of the speaker’s thoughts” . Furthermore:
The collegians were seen to set a good example for other forums on the visual channels in that they did not read from prepared scripts, but followed college platform style, consulting their reference cards only now and then; they debated as if the television audience were in the auditorium with them. While each orator was on teh air the other members could be seen listening and taking notes; only the collegiate yells and applause were missing from a natural forensic performance telecasters have recorded in their log as the first. 
The debate included maps and charts and even a film or two. I know next to nothing about collegiate debate. Does one side “win” the debate? If so, there’s no record of the winner.