Find out how, when and where to deal with topics that often present a why

A child’s favorite question may be “why?” But parents frequently don’t know all the answers.

CBS’ new series How’d They Do That? may be coming to the rescue.

Segments include the answer to “How do Tom and Sue Swick manage to lead a normal life when they have nine children under the age of 11?” In addition to providing a unique portrait of time management, this is a segment that could help parents appreciate smaller broods.

Another question: “How has Jesse White given hope and new direction to hundreds of kids from one of America’s worst housing projects, where only 150 fathers (among 12,000 residents) live at home with their families?”

Executive producer and nine-time Emmy winner Eric Schotz says, “The goal of the show is to tell you something you don’t know about something you know.”

“Kids have the natural curiosity that this show is based on,” he adds. “It’s more than just, ‘Why is the sky blue?’ As a kid, you’re always asking how did they do something. We took that umbrella concept and applied it to stories, and we tell those stories with a very distinctive point of view.”

Each episode of the reality series features stories from around the world. Some of the subjects explored will be Hollywood special effects, scientific breakthroughs and the wonders of nature.

Schotz adds that upcoming shows will tell how they train Shamu the whale, as well as how “the human calculator” (who adds, subtracts and divides 7 three-digit numbers faster than a calculator) operates.

“How’d They Do That?” airs two different episodes Wednesday (its regular night) and Saturday, 8-9 p.m., CBS. For ages 8 and up.

MORE FAMILY SHOWS

Ray Bolger provides the voice for Peter and the Magic Egg (Sunday 3:25-4 p.m. Disney), about a wisecracking bird who brings prosperity and laughter back to the people and animals in a Pennsylvania Dutch town. For ages 2 to 8.

It’s 1942. With what may seem to be an overactive imagination, young Harry is convinced that Nazi Spies (Sunday 7-8:30 p.m. Disney) have landed on the Eastern Seaboard. He monitors communications using a shortwave radio. Through his adventures, he discovers a plot to assassinate President Franklin Delano Roosevelt. For ages 7 and up .

You can’t judge a book by its cover. Apparently, you can’t judge a guy by his name either, which Clarissa learns on Clarissa Explains It All (Sunday noon-12:30 p.m. Nickelodeon). At Sam’s insistence, Clarissa agrees to go on a blind foursome date. When she learns her date’s name is Milton, she’s convinced he’s a geek . . . until she learns of his ponytail and rock-band membership, then she realizes that she may be the geek. For ages 7 and up.

CableACE Award-winning Avonlea (Monday 8-9 p.m. Disney) begins its fourth season. Celebrity guest stars will include Meg Tilly and Treat Williams. The series is based on the stories of Canadian author Lucy Maud Montgomery. For ages 7 and up.

In 1935, Rouben Mamoulian brought William Makepeace Thackeray’s “Vanity Fair” to life as Becky Sharp (Friday 4:30-6 p.m. AMC), with Miriam Hopkins in the title role of a self-involved girl striving for social success. While this likely required-reading story probably won’t be required until junior high, the moral of the tale is easily decipherable, as well as timeless. For ages 10 and up.