Seven-year-old Esmerelda Guzman cranked away on the bike pedals and tried to stay on a seat that was a bit too high for her.

But her spinning legs made the blender affixed to the back of the stationary bike go, and before she was finished, she had spun her way to a fruit smoothie.

"You do rounds, fast," she said, cheeks red from the effort at Southwest Community Park in Santa Rosa on Monday afternoon.

Guzman and scores of other children and their families turned out for one of five kick-off events in Sonoma County this week for the free summer lunch program.

The program was created to bridge the summertime gap when children who receive free or reduced-price lunches at school might not have access to a well-rounded midday meal, said Gail Atkins, program coordinator for the Redwood Empire Food Bank, which oversees meals at 48 sites across the county.

In Sonoma County, 45 percent of all students qualified for a free or reduced-price lunch in 2010-11, up from 23 percent in 2000-01.

The food bank's summer program started in 2004 with 15,000 meals served. Last year, 102,000 meals were served.

"Ever since the recession, we have just grown astronomically," Atkins said.

Across the state, more than 57 percent -- 6.1 million -- of California's school children qualified in 2010-11, up from 47 percent in 2000-01.

The food bank is the lead agency in Sonoma County, serving in 48 locations. Meals are also coordinated through the Boys and Girls Club, Santa Rosa City Schools and others.

"That's what makes it work in this county, because there are all of these partnerships," said Cathy Luellen-Aflague, director of child nutrition services for Santa Rosa City Schools. "Because we are all partnering together, it works."

School district crews are preparing meals to serve kids at 60 sites every weekday this summer, including those coordinated by the food bank, she said.

The food bank's program cost $303,000 last summer, when about 102,000 meals were served. The program is funded largely by the federal Summer Food Service Program but also relies on about 100 volunteers as well as grant funding.

Despite planning for more than 100,000 meals this summer, Atkins said she expects the summer program will only reach about 10 percent of the students who qualify for a free or reduced lunch during the school year.

How to reach the remaining 90 percent is a concern, she said.

"That is what we are worried about: What do they do? Where are they? I hope they are getting meals somewhere," she said.

Families were alerted to the free meals via fliers before the end of the school year, as well as through afterschool programs, automated phone calls and other outreach programs.

Kick-off festivities this week include garden activities and games to encourage kids to be more active in the summer.

"Oftentimes, during the summer they don't have structure like they do during the school year," said Jennifer McClendon, program director for Network for a Healthy California, which hosted the blender bike at Southwest Community Park.

Staff Writer Kerry Benefield writes an education blog at extracredit.blogs.pressdemocrat.com. She can be reached at 526-8671 or kerry.benefield@pressdemocrat.com.