Who knew the preschool set was so sophisticated about music and marketing? Animated versions of The Backstreet Boys appear on the cartoon special “Arthur: It’s Only Rock ‘n Roll” (7 p.m. Sunday, PBS).

For the uninitiated, Arthur is a bookish animated critter who wears glasses and a sweater. One of his pals, Muffy, obsesses about Nick Carter and the Backstreet Boys. This annoys her friend Francine, who is inspired to form her own rock ‘n’ roll band. She promises never to “sell out” like all of those boy bands.

When did second-graders begin worrying about crass commercialism and “selling out”? Some older viewers might wonder if PBS has sold out by pushing a commercial band on educational television.

For what it’s worth, the Backstreet Boys adapt remarkably well to a two-dimensional universe, look great as furry creatures and blend in with this gentle and often clever children’s cartoon.

Five years after the death of Princess Diana, CBS “honors” her memory with the TV movie “The Biographer: The Secret Life of Princess Di” (8 p.m. Sunday, CBS). “Biographer” shows how Diana used journalist Andrew Morton (played by Paul McGann) as a means to leak nasty tales about her royal in-laws to an eager tabloid press.

VH1 also looks to 1997 to celebrate the fifth anniversary of “Behind the Music” (8 p.m. Sunday), with a profile of Aerosmith. This is the original two-hour installment of the series, featuring interviews with Steven Tyler, Joe Perry, Tom Hamilton, Brad Whitford and Joey Kramer, as well as a chat with Tyler and his actress-daughter Liv Tyler.

While many critics and viewers loved the series “24,” some feared that they would lose track of the story if they missed a single episode. The FX Network celebrates Labor Day with a 24-hour “24” marathon, beginning at midnight Sunday.

“24” transpires in real time, following the events in the life of CIA agent Jack Bauer (Kiefer Sutherland) as he tries to stop an attempted assassination of a presidential candidate and find the kidnappers who have seized his daughter.

Gun battles, betrayals, bouts with amnesia, and one of the oddest political couples of all time make “24” compelling from beginning to end.

could have done without Dennis Hopper’s dreadful Balkan accent, but that’s a minor complaint. Buy plenty of blank tapes, and learn to set your VCR. This is one marathon worth watching in its entirety.

Today’s highlights

Notre Dame and Maryland meet in college football action (7 p.m., ABC).

Filmgoers howled at Mariah Carey’s contrived turn in the 2001 musical drama “Glitter” (7 p.m., HBO). This critically savaged film helped transform Carey from a diva into a punch line.

John Goodman is host for this repeat of “Saturday Night Live” (10:30 p.m., NBC), with musical guest Ja Rule.

Sunday’s highlights

Repeat reports scheduled on “60 Minutes” (6 p.m., CBS): a controversial Saudi prince; domestic violence in the U.S. military; Muslim schools in America.

Nathan Lane stars in the 1997 comedy “Mouse Hunt” (6 p.m., ABC).

A model goes missing on “Forensic Files” (7 p.m., NBC).

A decapitated corpse offers a heads-up clue on “Law & Order: Criminal Intent” (8 p.m., NBC)

A jilted bar-hopper goes ballistic on “Crime & Punishment” (9 p.m., NBC).

Cult choice

A filmmaker fan (actor and director Rob Reiner) examines the saga of his favorite British rock band in the wonderfully absurd 1984 fake documentary “This is Spinal Tap” (7 p.m. Saturday, AMC).