Sinclair Institute made many sex-education videos, distributed by Adam & Eve, but this one is the closest to hardcore porn content I've seen. Covering 4 topics: Fellatio, Cunnilingus, 69 and Anilingus, it features an endless array of couples performing explicit sex, minus coitus.
Two familiar actors perform: Eric Masterson and Julian St. Jox, just another day at the office amongst their thousands of credits. The rest are likely amateurs, including an older couple, the male partner of which has a small dick, quite rare in 21st Century porn.
Voice-over narration gives the viewer tips regarding positions, including suspension where a hanging seat supposedly helps achieving deep-throat (but merely looks awkward).
It's difficult, viewing this video without an agenda, to consider it as sex education: the constant XXX (split-screen lamely with photos of vintage erotic sculptures) action is porn by definition.