"Jim Hensons Frog School" was announced around the time of Swamp Years but was gonna be a similar thing but as a TV series. Here's an article on it :-
Henson Preschool TV Shows in Development
from Kidscreen Magazine, January 3, 2002
by Mike Connell
Jim Henson Television has decided to give the world an inside look into what made Kermit the reptile he is today. Jim Henson's Frog School is a live action/Muppet preschool comedy (with some short animated segments) that centers around Kermie's adolescent years at Frog School, where his education was based on an ancient frog philosophy stressing virtue and responsibility for one's actions towards others and the environment. Jim Henson's daughter Lisa will serve as executive producer on the 26 x half-hour series, which is budgeted at between $350,000 and $400,000 per episode. Animated sequences illustrate fables and myths from around the world that are used to teach the reptilian students about life outside the swamp.
The project is part of a new Henson curriculum focus guided by an educational advisory board established to help the company follow through on its assertion that TV can change people's lives, says Juliet Blake, president of Jim Henson Television US. Henson is hoping to carve a niche with preschool shows that tackle school readiness, Blake explains, from both an emotional and curriculum perspective. She likens Frog School to Bear in the Big Blue House, the producer of which -- Alex Rockwell -- is also on-board for the new Henson offering.
Another preschool project under the advisory board's guidance is Harry and Lulu. Budgeted closer to $300,000 per ep, this 26 x half-hour animated series stars a five-year-old and her brand-new stuffed dog. When Lulu's parents turn off the lights at night, Harry comes to life and starts telling her about his world travels. Lulu's a little skeptical, so Harry leads her through a magical doggie door that's a portal to anywhere in the world. The series was developed for preschoolers about to make the transition to kindergarten, the idea being to introduce them to the fact that there's a big world outside their neighborhood full of different kinds of kids.
Both Jim Henson's Frog School and Harry and Lulu are in early development, and delivery dates weren't available at press time.