Kids' music has grown up. An explosion in creativity has revived a once-insipid musical backwater dominated by earnest middle-aged men and mewling purple dinosaurs.

Dozens of artists, many of them former indie rockers, have pushed the musical boundaries and made it possible for parents and children to listen to music together again - as a family.

Although the music industry is in turmoil, with CD sales tumbling, albums for toddlers and young children are soaring. Last year children's music sales grew more than 38 percent, from 12.3 million to 17.1 million units, according to Nielsen SoundScan.

And these acts are part of the lucrative summer touring season, from Juno's unlikely folksinger Kimya Dawson at the Philadelphia Folk Festival to the Wiggles at the Spectrum and the giant Disney Music Block Party Tour, setting up for three days in Fairmount Park.

Veteran acts like They Might Be Giants sell more albums for children than they ever did for adults. TMBG's hilarious Here Come the ABCs has sold more than 94,000 copies since its release in 2005 and remains an Amazon best seller. Here Come the 123s, released in February by Disney, has moved 40,000 copies - a healthy number for an independent music act in any genre.

Dan Zanes, the shock-haired former rocker, has built a cottage industry with a series of homespun albums, eclipsing his previous career as leader of the Del Fuegos.

Even one-hit wonders have entered the fray and scored minor triumphs. Lisa Loeb, best known for "Stay" on 1994's Reality Bites sound track, just issued her second children's disc, Camp Lisa, a delightful collection of summer camp songs.

It's obvious F. Scott Fitzgerald was wrong. There are second acts in American lives - only they're being played out before family audiences, not just adults.

Ralph Covert, 46, was leader of the '90s alternative rock band the Bad Examples. For more than a decade, his quartet slogged from bar to bar and released some fine records, but never managed to break out of Chicago.

Ralph's World, his side project for children, mushroomed into a full-time job. Now recording for Disney, Covert has become one of the genre's superstars.

"We never played the Fillmore with the Bad Examples," said Covert. "But we did with Ralph's World."

Ralph's World stands to become even more densely populated when the band headlines the Disney Music Block Party, a nine-city tour that sets down in Sweet Briar Field in Fairmount Park for three days, beginning Friday.

Billed by organizers as an Ozzfest for preschoolers, the Disney festival also features Dan Zanes & Friends, Choo Choo Soul, and the Imagination Movers.

"This has been a truly outstanding year for kids

and family music," said Kathy O'Connell, the effervescent hostess of Kids Corner, a radio show for children produced daily at WXPN-FM (88.5) in Philadelphia.

"When I first started, it was a whole different world," said O'Connell, who created the Peabody Award-winning show 20 years ago. "We had Pete Seeger, Ella Jenkins and Tom Paxton. But we also played Cyndi Lauper and Madonna. There just wasn't that much stuff to play."

Now there's so much material O'Connell doesn't have time to air former staples like "Weird Al" Yankovic and Spike Jones.

She's particularly hot on two new albums: Pop Fly, by Justin Roberts, a former Montessori teacher turned full-time kids' rocker from Chicago, and Tabby Road by Recess Monkey, a Beatles-esque quartet of elementary school teachers from Seattle.

And the year isn't over. Roots-rockers Los Lobos are releasing a collection of Disney classics in November, and Putumayo is putting out Sesame Street Playground, with songs from around the world, in September.