Christmas Eve on Sesame Street (1978)
Beginning in November of 1969, The Children's Television Workshop began producing the show on PBS. It featured Actors and kids along with Jim Henson's muppets (Jim is a Mississippi native like me) and was a general education show that tackled reading, arithmetic, language, culture, music and social interaction.
In 1978, PBS produced a primetime Holiday special that featured the cast on Christmas Eve.
Here is part one of the program (all parts are available on Youtube)