Rich in fantasy, action and loud, frantic music, Nickelodeon’s new cartoon “Chalkzone” (7:30 p.m.) is certain to delight children and drive parents from the TV room. OK Â parents who like the loud, frantic music might stick around.

“Chalkzone” concerns one Rudy Tabootie (the voice of E.G. Daily), a shy 10-year-old who escapes the boredom of school and the brutality of bullies by retreating into his own cartoon drawings. One day he discovers a box of magic chalk that enables him to escape into the enchanted ChalkZone, a place where everything that has ever been drawn in chalk and then erased reappears and lives forever. As the repository of childhood imagination, the zone contains legions of robots, spiders, diabolical snakes and other wacky creations.

Luckily for Rudy, he once created a super-hero assistant named Snap (Candi Milo), who becomes his ambassador and guide to the weird ways of the ChalkZone. Once there, Rudy can solve his problems only by drawing solutions with his magic chalk. In addition to Snap, Rudy spends a lot of time with the myopic math genius Penny (Hynden Walch). She even gets to accompany him to the Zone during recess and when their hapless teacher is distracted by a slide show or other boring classroom stuff.

Savvy cartoon fans might find Rudy’s voice familiar. Daily provides the voice of Tommy Pickles on “Rugrats.” She also gave voice to the title critter in “Babe: Pig in the City” and to Buttercup on the Cartoon Network’s “The Powerpuff Girls.”

 Is the dotcom revolution over? Or just on hiatus? Tonight, The Sundance Channel launches its own hi-tech marathon, screening three recent, provocative documentaries about computer culture.

Directed by J.T.S. Moore, “Revolution OS” (5 p.m.) examines the hackers, engineers and software-savvy idealists who challenge Microsoft’s domination and champion the Open Source movement. Interviews include Linus Torvalds, who created the Linux system as a 21-year-old college student

“E-dreams” (6:25 p.m.) follows the two investment bankers behind the Kozmo.com Internet delivery service that flourished in the late 1990s but joined the ranks of the stocks vaporized in the Internet stock plunge of April 2000.

The critically acclaimed “Startup.com” (8 p.m.) follows two entrepreneurs and high school buddies as they try to secure funding for their site, govWorks. It’s more intimate, and interesting, than any “Real World” rip-off.

These three films will repeat on Sunday afternoon, beginning at noon, and Sunday, March 31, beginning at 8 p.m.

Tonight’s other highlights

 The NCAA Basketball Tournament (6:30 p.m., CBS) continues.

 Syd’s old boyfriend has made it big in network television on “Providence” (7 p.m., NBC).

 Five families retreat to Fiji to compete and cooperate on the new reality game show “Under One Roof” (7 p.m., UPN).

 Profiled on “Biography” (7 p.m., A&E): “Harry Potter” creator J.K. Rowling.

 Scheduled on “Dateline” (8 p.m., NBC): an examination of a “parents first” policy that mandates that a foster child be taken from nurturing foster parents and returned to her biological parent, despite past evidence of neglect.

 The Stages find a baby on the doorstep with Rick’s name on it on “Maybe it’s Me” (8:30 p.m., WB).

 Investigating a baby-snatching ring on a repeat of “Law & Order: Special Victims Unit” (9 p.m., NBC).

 Scheduled on “20/20” (9p.m., ABC): A teen’s death from ecstasy; an interview with Sarah Brady; the enduring appeal of the musical “Oklahoma!”

Cult choice

 Marlon Brando and Val Kilmer star in the 1996 remake of “The Island of Dr. Moreau” (10 p.m., USA).