Sixty million dollars is a lot of money. The Las Lomitas Elementary School District is hoping voters think it'll be money well spent and will approve Measure S, a $60 million bond measure, on the Nov. 5 ballot. The measure must win favor with at least 55 percent of the voters to pass.

Like other school districts in the Almanac's coverage area, Las Lomitas is bracing for further growth in enrollment, which has risen 40 percent during the past decade. Carolyn Chow, the district's chief business officer, said the schools expect a net growth of 46 students next year, after adding 70 this year.

The bond measure would allow the two schools in the district -- Las Lomitas (K-3) in Atherton and La Entrada (4-8) in Menlo Park -- to build new two-story buildings, eliminate 18 portable classrooms, and renovate existing facilities, according to the ballot statement. It would not include complete reconstruction of the campuses, but instead would tear down up to one-third of the current structures to make room for new classrooms, according to the school board.

The California constitution requires the listing of specific projects to be funded from the bond revenue. Specific projects earmarked for Measure S money include replacing plumbing infrastructure; updating the electrical system to allow wireless networking; replacing windows and other environmental features to improve energy efficiency; and adding sprinklers as well as fire safety doors.

The district estimates that property owners would be assessed $30 a year per $100,000 of taxable property. According to the school board, the payments would likely be ongoing through 2045. The measure calls for the appointment of a citizens' oversight committee to monitor how the bond money gets spent.

The school board voted 5-0 in August to put the bond measure on the ballot.

Diana Sunshine, co-chair of the "Yes on S" committee, said the district has seen "a great wave of families" moving into the area from other Bay Area cities to attend a top-performing school like La Entrada. The district had 900 students when her daughter, now in the seventh grade, started attending. Now there are about 1,400. About 20 percent of current students attend class in the portables.

The school district does have other revenue sources to draw upon, namely income from two other properties leased out at a point when enrollment fell decades ago and the district closed its own schools on those sites; and the Las Lomitas Education Foundation, which raised $2.8 million for the district for the 2013-14 school year. Those two sources combined contribute 25 percent of the district's annual revenue, Ms. Sunshine said, and allow the schools to continue offering courses that other public schools have eliminated, such as four foreign language options: Mandarin, Latin, Spanish and French. In addition, the district collects income from an annual $311 parcel tax approved in 2007.

The district has leased one campus, in Ladera, to Woodland School, a private elementary school, for more than 30 years. The other, in Menlo Park, has been rented out to Phillips Brooks, also a private elementary school, for about the same amount of time.

"We looked at taking back the lease properties, but decided against that because it gives us really good, strong annual revenue," Ms. Sunshine explained.

School board president Richard Ginn said additional factors led to the decision not to pursue reclaiming the leased properties. The Ladera site, which is several miles away and west of Interstate 280, would create a geographical divide for the school community. And while the district would lose significant revenue from the lease of the sites, it would have to spend more for additional staff.

"We would still have to go to voters for money," Mr. Ginn said.

Beyond replacing all portables, the specifics of how the bond money would be spent if the measure passes will be something for the school board and community to work on, according to Mr. Ginn.

"The main priority is classrooms for kids," he said. If the bond measure passes, the school board will get to work on what specifically will be done, and create a committee to sort through the remaining priorities.

No one presented a ballot argument against Measure S, which may not be surprising in light of what Ms. Sunshine described as overwhelming support for the bond measure among parents and community members.

"This is our first bond in 12 years," she said. "We take this very seriously and we want to be as prudent as we can."

Renee Batti contributed to this story.