Frank Zappa live at TTG Studios, 1966 (via Zappateers)
 
It must have been thrilling, the teacher threading the film into the projector and the Mothers of Invention bursting out of the chalkboard in full color. The instructional movie Sex in Today’s World, a/k/a Sex in the Sixties, presented by Focus Education, Inc., incorporates a few short clips of the Freak Out!-period Mothers driving an LA audience into a Bacchic frenzy.

Román García Albertos’s valuable Zappa videography says this footage was shot at Hollywood’s TTG Studios in 1966 for broadcast on The David Susskind Show. The videography suggests Sex in the Sixties was originally broadcast on ABC, but judging from the number of splices toward the beginning of the version on YouTube, the source is a sex-ed print that saw legit classroom use.
 

The Mothers live at TTG Studios, 1966 (via Zappateers)
 
Something Weird included Sex in Today’s World in the collection Sex Hygiene Scare Films, Volume 2. Here’s the synopsis from their catalog:

Sex in Today’s World (color), “an examination of sex in the 1960’s,” is a time capsule which neatly captures many of the conflicting attitudes of a cross section of people—doctor, psychologist, professors, students, and preachers—caught in the sexual turbulence of 1966. The so-called Sexual Revolution happened so quickly and with such across-the-board pervasiveness that this little film, like most of the people interviewed, seems not only dazed, but trying to catch its breath. It also includes some great glimpses of mid-sixties adult book stores, 42nd Street in its glorious grindhouse heyday, Bunnies doing a go-go at a Playboy Club and, most surprising of all, concert footage of FRANK ZAPPA and THE MOTHERS OF INVENTION! The inevitable conclusion: Yeah, there’s sure a lot of sex out there!

Incidentally, that’s Del Casher, inventor of the wah-wah pedal, sitting in on guitar.