DALLAS - Life for the Washington family has changed. Instead of fast food for dinner, they have grilled chicken and vegetables. Sugary drinks have been replaced with diet soda. Frisbee games in their yard have encroached on television time.

It's been more than two months since the Washingtons — Bill, Sue and their 9-year-old daughter Alana — completed a family program for children struggling with their weight and now they're trying to stick to their nutrition and fitness goals.

"It's been gradual," said Bill Washington on a summer afternoon as Alana snacked on grapes, low-fat crackers and low-fat cheese. "I've noticed her willingness to participate and be active in healthy decisions."

Alana misses doughnuts, but concedes that she enjoys much of the healthier fare her family has been eating. She prefers baked Cheetos to the regular ones, loves diet Mountain Dew and has even developed a love for snow peas.

The three-month program — called Dean Foods LEAN (Lifestyle, Exercise and Nutrition) Families Program — offered at Children's Medical Center Dallas focuses on making fitness and nutrition changes for the whole family.

"We're really trying to teach them skills they can use for the rest of their lives," said Dr. LeAnn Kridelbaugh, the program's medical director.

The Dallas program is one of many across the United States trying to tackle the issue of childhood obesity — more than one-third of American children are overweight. At least 95 children's hospitals have similar programs, according to a survey by the National Association of Children's Hospitals and Related Institutions and Columbus Children's Hospital in Ohio.

A recent study in the Journal of the American Medical Association showed some encouraging results for intensive family programs. It compared weight management counseling for youths with a comprehensive family based program in which participants met much more frequently.

Children in the family programs kept up their healthier routine the entire year. As they grew taller, their body mass index fell even though their weight stayed the same. Those who only got counseling had an increase in body mass index and weight.

The Dallas program has enrolled about 90 children since it began last year, and about 80 percent stayed with it to the end. It's geared for children ages 6 to 11 with a body mass index in the obesity range. About half of the participants either maintain or decrease their body mass index.

The program costs about $1,300 per family with discounts for those who don't have insurance that covers it.

For small children, Kridelbaugh said the focus is on developing better eating and fitness habits rather than weight loss. With proper nutrition and exercise, height and weight should balance out as they grow.

"The philosophy is not 'Let's get you to lose weight in 12 weeks,'" Kridelbaugh said. "What we're trying to teach them is eating habits and activity habits that you do for a lifetime."

Dallas pediatrician Marjorie Milici has referred about 15 families to the Children's program.

"We're seeing so many patients, I don't have the time to do the education they're doing," Milici said.

Each weekly 2-hour session begins with a healthy snack and a review of the previous week's goals. Parents and children break into separate groups for their lesson, then regroup to set the next week's targets.

Three weeks into the program, Jessica Duckworth's 5-year-old daughter EmmaLee was already getting the idea. She told her grandfather, who often showered her with candy, that she couldn't eat sweets all the time. On his next visit, he brought fruit.

"It's been easier for her than it has been for us," Jessica Duckworth said.

EmmaLee's mom and grandmother said a trip to the Dallas Zoo revealed her progress. Usually they bring a wagon for when Jessica tired but this time they left it home. It turned out that EmmaLee, full of energy and pep, didn't need it anyway.

For Alana Washington, it's been a summer of swimming and camp. She's grown almost an inch while her weight has remained constant.

"Prior to this, it was constantly gaining no matter what," Sue Washington said of her daughter. "Now the brakes are on."