Square One TV, PBS
IMDb; Retro Junk; TV.com; TV Tropes; Wikipedia
Anyway, um... this show was funny. The point was to teach math to kids. I think the people in it knew how uncool they were, and I think they didn't bloody well care, they were just having fun doing their jobs. That's what it looked like to me, anyway. It's a prime example of "so uncool, it's cool." Anyway, yeah, funny stuff, all the dumb sketches and songs and whatnot. Great fun. Occasionally there was even someone sort of famous on, such as Bobby McFerrin.
Every episode would end with a Mathnet (fansite; Wikipedia) story (kinda like how every episode of 3-2-1 Contact would end with a "Bloodhound Gang" story). Mathnet was kind of a parody of "Dragnet" (a show that's before my time), about these sort of police who solved crimes using math, or whatever. Originally the cops were George Frankly and Kate Monday, though Kate was later replaced by Pat Tuesday. And there were some other characters on the show who I don't remember quite as well. Anyway, each case would take them five episodes to solve (since Square One aired five episodes per week, it took that long to get through a Mathnet case).
Anyway, I remember both Square One and Mathnet fondly, and still occasionally think of some of the songs from Square One. And sketches, and whatnot. It was great.