"Unfortunately, for some of [the campers] this is the only tennis they play during the year and we're trying to change that," said Zambrano, who also uses it as a chance to expose families to the programs offered at the Fremont Tennis Center.
Odria Boghozian, an 11-year-old incoming sixth grader at John Muir Elementary, has been attending the LA84 Foundation camp at Fremont Tennis Center for the past three summers.
"It's fun," said Boghozian of why she keeps coming back. "Every year you come, you learn new things and you keep moving on and having fun with your friends."
Boghozian was first introduced to tennis at the 2009 camp headed by Zambrano. After her second summer with Zambrano she began challenging her friends to matches, which she said she rarely loses, thanks to his coaching.
"I think it's a sport you'll always like to play and compete with others," Boghozian said. "I wasn't really good at first but now I am getting better and better every year I come. I set goals every year and I try to hit as many as I can."
Not all campers are as advanced as Boghozian, though. Josh Tamari, a 10 year old, is still working on consistently getting his shots to go over the net and land in play.
"My mom taught me [tennis] the first time, but I have been hitting really high so I keep coming back to work on it," Tamara said.
Campers are divided into one of two groups based on skill. Several camp counselors, who are mostly former Zambrano students or members of Zambrano's teams, help Zambrano manage the group of about 60 kids.
"I have a great group of volunteers — my ex-students," Zambrano said. "If they dropped I don't know what I would do, but they keep coming back. They are all in college, but they keep coming back so that makes it a lot more fun. They run half the program, I am just directing them."
Clayton Pauff, an incoming senior and No. 1 singles player at Burbank High, has served as a camp counselor with Zambrano all four years.
"I used to take lessons with Coach Ron and ever since then we've been friends," Pauff said. "I like helping out and working with the kids.
"It's cool passing down what I know to them and trying to get them into the sport and showing them how much fun it is. I will probably be playing this for the rest of my life."
That's exactly what Zambrano wants to hear from everyone who comes through his camp.
"I still have from four years ago a group of four or five eighth graders that might play in high school," Zambrano said. "That's the idea, to increase the tennis around the area."