School districts around the Bay Area are spying on their own students — often with private investigators — just to make sure the kids really live where they say they do.

Sometimes, private eyes surreptitiously photograph the youngsters as they come and go from homes suspected of being fronts. Sometimes, they lie about who and what they’re doing in hopes people unwittingly will rat the kids out.

This schoolhouse subterfuge tumbled into the open last month when the Orinda Union School District kicked out a 7-year-old Latina it erroneously believed did not reside in the tony, mostly white suburb. But in mostly affluent districts from Los Gatos to Palo Alto to Mill Valley, residency checks have been standard operating procedure for years.

Convinced that duplicitous parents are claiming Junior lives with Grandma to get him a better education, school administrators believe they have to expose the fraud so they can protect scarce resources for the kids who actually live in their community. But their tactics are raising hackles.

“We’re very concerned to know that students are being surveilled,” said Linnea Nelson, education equity staff attorney for the American Civil Liberties Union. “I question the resources put into that method when there seems to be much simpler ways to determine if someone lives in the district.”

To make the case that Vivian, the 7-year-old, did not live in Orinda, a private investigator hired by the district nosed around the girl’s old neighborhood in Bay Point, passing himself off as a car insurance investigator when he spoke to neighbors and to the girl’s mother.

The district later reversed itself and allowed the girl to stay at the school after a story in this newspaper recounted that Vivian’s mother was a live-in nanny for an Orinda couple, and that her primary residence was their home. The paper is not using Vivian’s last name for security reasons.

“It seems excessive for a school district to go straight to hiring a private investigator when questions of residency arise,” said Miriam Storch, who employs Vivian’s mom. “Most people are reasonable, and we’re talking about parents here, not criminals. When ordinary people are doing something wrong and you confront them about it, they’re probably going to admit it.”

The small Orinda district said it frequently uses investigators because it has no one on staff able to handle such queries. This newspaper’s survey of many Bay Area school districts, large and small, found that using private eyes is common.

Several high-performing districts throughout the Bay Area divulge on registration forms that investigators might be used if questions of residency come up.

According to the Los Gatos Union School District policy: “The district will actively investigate all cases where it has reason to believe that residency status has changed and/or false information has been provided, including the use of private investigators to verify residency status.” Parents are warned they can be criminally liable if they provide false information.

San Francisco Unified also warns parents that it uses private investigators, although spokeswoman Gentle Blythe said it largely assigns the task to in-house employees who must identify themselves as working for the district. The district’s website urges readers to “Report residency fraud!” with a confidential telephone hotline number and email tip line. The recorded phone hotline message asks for a student’s name, school, grade level and “alleged address,” promising to keep the report confidential.

A 2010 district probe resulted in the dismissal of a couple hundred students with faulty addresses, and their parents were socked with bills ranging from $500 to $4,500 for the investigation, Blythe said.

Chris Reynolds, president of California Association of Licensed Investigators, said the investigations usually begin with public database searches, but the next step is surveillance, involving photographing the child coming and going from a suspected residence over a number of days, he said.

“It’s the only way to verify,” Reynolds said. “Families will invariably say, ‘Prove it.'”

A run-of-the-mill investigation can run from $1,000 to $2,500, he said.

As school funds dry up, Reynolds said the demand for residency checks has increased. Many of his cases involve special-needs students, as a single child can cost a district more than $1 million in services during progression from kindergarten through high school.

In a 2010 San Jose Unified School District case, the parents of a special-needs student challenged the district’s dismissal of their middle school child over residency. In its decision, the district cited a private investigator who had observed the parents’ house 19 times and the grandmother’s house 10 times. The investigator, hired by the district for two months, documented the comings and goings of inhabitants from 100 yards away. A judge later determined the boy lived within the district’s boundaries, according to court documents.

Oakland Unified will hire an investigator when it believes a special-needs student might reside outside its boundaries, said spokesman Troy Flint.

“We’re so strapped for resources in that department,” he said. “The caseloads are heavier than we want them … and they’re very costly.”

The job description for this type of investigative work reveals just how steady — and sensitive — it can be. Dinolt, Becnel & Wells, a Washington, D.C.-based private eye firm, promotes its student surveillance capabilities on its website with a detailed description of how it does the work.

“Because we were following children, this surveillance had to be handled with the utmost delicacy,” the website explains. “Naturally, the public is very sensitive to people taking pictures of kids in public, and the last thing we wanted was to cause any anxiety over our investigations. To lessen the chances of detection, we often used multiple investigator teams — sometimes with as many as five investigators tailing a single subject — and a 300 mm lens to observe students and their families from a very safe distance.”

Other districts have chosen a different tack. Fremont Unified, a large district with 42 schools and about 34,000 students, declines to use private investigators, instead opting for principals or student support services staff who make home visits.

“We do not conduct surveillance but visit the residence to talk with the family,” said Superintendent Jim Morris, indicating that occurs about five to 10 times a year. “That’s the way we have always done it, and it has been effective for us.”

Palo Alto Unified School District employs a part-time residency officer, said spokeswoman Tabitha Kappeler-Hurley. But on rare occasions it hires a private investigator to assist, she said, and the work can include surveillance and photographs. She said the outside investigators are provided with a district ID in case there are questions.

Jesus “Jesse” Zuniga Jr., a retired Hayward and Tracy police officer, according to his LinkedIn profile, investigated Vivian, the Orinda student. He gave his business card to the girl’s mother after saying he was looking into an auto accident involving her car — there was no such accident — and asking where she lived. The girl had spent extra time in Bay Point because her great grandmother, who lived there, had been ill, which may have led to the mistaken conclusion she was not an Orinda resident.

In a phone call, Zuniga declined to talk about the specifics of the case. However, he said it’s common for those in his profession to make up a story to hide their true purpose.

Reynolds, head of the licensed investigators group, said such pretexts, or fibs, are legal but not often necessary in school residency probes because the investigator usually never talks to a parent.

Such tactics bother Storch, who said she hopes Vivian’s case launches a review of how districts conduct such investigations.

“How students are identified for investigation, how an investigation is deemed necessary, and how those investigations are conducted needs to be reviewed and made public knowledge,” she said. “I think we can all work together to come up with a better system that everyone is comfortable with.”

Contact Matthias Gafni at 925-952-5026. Follow him at Twitter.com/mgafni.