What do you like best about your family's car?

At big car manufacturing companies, there are plenty of adults trying to figure out what's in your head. And in your hands. And in your backpack.

"The voice of children is very strong in the development of our products -- they play a key role in the development of features," said Ed Larocque, whose job is making people in the United States want to buy Toyota cars, trucks and vans.

Larocque and other top auto executives are concerned about what features kids like to have in vehicles because car companies want to get younger people buying their products. The average age of a Toyota Camry buyer, for example, is 55. By coming up with gadgets that children love, carmakers hope to get more young parents as customers.

What are the gadgets that kids love? Lots of cup holders, places to put CDs and DVDs and portable games and, of course, in-car entertainment systems.

It used to be that car companies asked parents what they wanted in family cars. The result was lots of great safety features. Those are important, of course, but they just don't have the same impact on kids as a DVD player with wireless headphones and a Game Boy port.

These days, auto manufacturers are developing kid-friendly cars by actually talking to kids, and even videotaping families as they use their cars. General Motors gave early versions of its Buick Terazza, Pontiac Montana and Chevy Uplander to 30 families last summer and had them drive from Detroit to Orlando so the design team could find out what kids really want in a vehicle.

What kids want the most, it seems, is to watch movies and play games -- just like they can at home.

"That was huge in my house -- every so often we'd have to look back and make sure the kids were still in the car because of how quiet it got," said Ken Parkinson, who is in charge of exterior design for General Motors's trucks and SUVs. "Now you can hook your iPod right into the stereo of the vehicle."

Parkinson, who has worked on interior and exterior design for the giant automaker, says the best feedback for family vehicles comes from the designers who have kids. They not only talk to their kids at home, they sometimes bring their children to work and show them the newest ideas.

And everything aimed at kids gets a major durability test.

"You don't want it to be something that once . . . kids are climbing around back there, they step on it and it breaks," Parkinson said.

-- Margaret Webb Pressler

General Motors and other companies are using families to test tricked-out versions of new vehicles, including easy-to-reach storage space for DVDs and snacks. The automakers hope that new features will lead to more sales.