This year's nine-week session started June 28 to steady demand, officials said.
The high demand comes as officials pursue a "very aggressive" construction schedule to make sure the pool meets its scheduled summer 2011 opening after design changes and plan check delays slowed the process.
"It doesn't do us any good to finish it up in October because then we'll have to wait another year, and it's a new facility that will sit vacant not being used," said Community Services & Parks Director George Chapjian. "We are going to push hard to get that done."
Pacific Park previously had a public pool, but it was demolished as part of the city's joint Edison Elementary School project in 2003, leaving the aquatics programs at local high schools as the only community swim option.
The City Council last month approved soliciting construction bids, but officials have had to wait on receiving approval from Los Angeles County.
Officials now hope to break ground by September, leaving only nine months until the scheduled May 2011 debut.
Still, Capital Projects Manager Dave Ahern said he was confident they can open the pool on time, although landscaping and other finishing touches may continue after the pool opens.
"We can get the pool open and running, then do landscaping while that's occurring," he said. "While it's always nice to have everything done, the goal is to be open at the end of May."
Mayor Ara Najarian, who has championed the $5-million "L-shaped" pool, said the turnout at high school pools shows the need for a public city pool.
"That just goes to show you what a huge demand for swimming lessons there is from the community. I think we owe it to meet those demands," he said. "Too many of our kids are forced out of the shared pools that we have at the school district and are not able to pursue lessons, activities and free play."
Open swim time on the weekends has also seen high demand, with more than 100 participants at each pool, Maglio said. She added that weekday open swim times have seen lower attendance so far, likely because it conflicts with summer school.
Along with lessons, the program includes water polo teams, a junior lifeguard academy, open swim time and other special events. The city also operates wading pools at some local parks.
Maglio said public swimming lessons go beyond summer fun and exercise by also teaching children important water safety skills.
Drowning is a leading cause of accidental death of children up to age 14, she said.
"Swimming lessons are extremely important because they provide a life skill," she said. "It provides them with the opportunity to learn, at the minimum, the basics of how to keep themselves safe in the water so they can avoid drowning."