Both seasons of the show are vasty difference in terms of format and tone. The first season is presented in an anthology format, featuring different stories each week featuring at least one recognizable character from the Dr. Seuss library (such as the Grinch and Horton the Elephant). The Cat in the Hat and his Little Cats served as hosts of the series, bookending each story while occasionally interfering with the events.
The second season completely changed the format of the show, losing the anthology basis and instead becoming more like the typical preschool programing of the time, taking on a more light-hearted approach. In addition to a new theme sequence, the Cat in the Hat and the Little Cats had an increased presence, with their sequences (taking place in the Cat's Playhouse, the only non computer generated set in the show) taking up the majority of the show. During each show, the Cat would consult the Wubbuloscope, where short stories feature other Dr. Seuss characters pertaining to the theme of the episode.
- Bruce Lanoil as The Cat in the Hat (season 1), Fox in Socks (season 1)
- Martin P. Robinson as The Cat in the Hat (season 2)
- Anthony Asbury as The Grinch, Thidwick the Big-Hearted Moose, Yertle the Turtle, Terrence McBird, Little Cat Z (season 2)
- John Kennedy as Horton the Elephant, Little Cat C, Mr. Knox, Sam-I-Am
- Kathryn Mullen as Morton the Elephant Bird (season 1), Little Cat A (season 1), Junior Kangaroo (season 1)
- Stephanie D'Abruzzo as Jane Kangaroo, Max, Little Cat B, Pam-I-Am, Sarah Hall-Small
- Leslie Carrara as Little Cat A (season 2), Morton the Elephant Bird (season 2)
- Tim Lagasse as Fox in Socks (season 2), Junior Kangaroo (season 2), Little Cat P (season 2)
Guest or background/assistant puppeteers included Pam Arciero, Heather Asch, Bill Barretta, Camille Bonora, Kevin Clash, Vicki Kenderes-Eibner, Jim Kroupa, Joey Mazzarino, Brian Muehl, Jerry Nelson, John Tartaglia, and Nikki Tilroe.
- The series was unique in that the computer generated backgrounds were animated in real-time, allowing for such things as the scenery moving as the characters moved and objects moved when interacted with.
- Executive Producer: Michael K. Frith (season 1), David Steven Cohen (season 1), Brian Henson, Stephanie Simpson (season 2)
- Produced by: Lauren Gray (season 1), Bob Stein (season 1), Jerry Kupfer (season 2), David Gumpel
- Directors: David Gumpel, John Leo, Kathryn Mullen (season 2), David Nebel, Scott Preston, Emily Squires (season 2), Rick Velleu (season 2), Dean Gordon (season 2), Anthony Asbury (season 2), Steve Feldman (season 2)
- Writers: Carin Greenberg Baker, Lou Berger, David Steven Cohen, Gary Cooper, Annie Evans, Adam Felber (season 2), Phil Lollar, Bill Marsilii, Jay Martel (season 2), Allan Neuwirth, Will Ryan, Mo Rocca (season 2), Craig Shemin, Stephanie Simpson (season 2), Belinda Ward, Jonathan Greenberg (season 2)
- Consulting Producer: Will Ryan
- Production Designer: Ed Eyth
- Music: Bob Golden (season 2) Joe Carroll (season 1), Stephen Lawrence (season 2), Art Labriola (season 2), Peter Thom (season 1), Mark Gray (season 1), Glen Daum (season 1), John Lissauer (season 1)
- Theme Song: Bob Golden & Jack Feldman (season 2)
- Songs: Bob Golden, Jack Feldman, Rusty Magee, Joe Carroll, Mark Gray, Peter Thom, Russ Irwin, Bill Marsilii, Rich Mendoza, Steve Klapper, David Steven Cohen, Hal J. Cohen, Zina Goldrich, David Kinnoin, John Hoke, Bob Stillman, Will Ryan, Craig Shemin
- Puppet Captain: Kathryn Mullen (season 1), John E. Kennedy (season 2)
- Technical Director: Tom Guadarrama