When it came time to choose an elementary school for Claire, the couple applied for an interdistrict transfer to a San Francisco public school. Luckily, they were able to meet one of several qualifications that districts require in order to allow a student to leave one public school district to attend another.

They weighed the benefits of keeping Claire in an Oakland public school, but ultimately decided to preserve what family time they could. So they took the transfer, and the BART rides kept going.

Hundreds of Oakland families have asked to enroll their children in schools outside the district, but transfers into the district are rare. Only a few dozen non-Oakland families apply to get into Oakland public schools. This migration of students from Oakland to Berkeley, Piedmont, San Leandro and other cities concerns the district, which now wants to study these families making the choice to leave.

"It’s evidence of us not appealing to the community fully," said Charles Wilson, new director of district enrollment.

There are holes in the data kept by Oakland Unified. A KQED analysis found that though the district knows how many students requested transfers for recent school years -- 1,522 for 2015-16, for instance -- it doesn't keep an exact count of how many requests it receives or how many are approved.

Wilson said digital record keeping for interdistrict transfers started only a few years ago, and there was no formal process to collect the data.

Wilson said his goal is to figure out who these students are and then hold focus groups with the families to see what the district can learn about why they’re choosing to leave -- beyond the reasons they’re giving for requesting the transfers.

“It is sort of the canary in the coal mine of the larger symptom of why are people not choosing Oakland public schools,” said Wilson.

The district estimates roughly a quarter of Oakland's school-age children are choosing schools other than Oakland public and charter schools. That’s about 16,000 students. Most are choosing private schools, but there isn’t a lot of information on these families that can help the district address their reasons for opting out of the district.

Why Families Say They're Requesting Other Districts

Families must meet certain criteria to be approved for an interdistrict transfer. Legitimate reasons include: the student's parent works in another district, the student has special health or safety concerns, a sibling attends another district, or a special program exists in another district.

But requesting a transfer just to attend a better school elsewhere doesn’t work, said Wilson. The accepting district also has to approve the transfer.

[chartSchoolReasons]

Data from the transfer application don’t always tell the full story.

Sara Diamond said the main reason she requested a transfer was to preserve family time. But she acknowledged that school quality did play a small role.

“Our general sense after comparing schools in both districts was that in general San Francisco was doing a better job at that time,” she said.

The primary reason interdistrict transfers are granted is because a parent or guardian works in the requested district. This makes up more than one-third of Oakland requests to transfer out.

Last year, 70 families said they wanted to transfer out because of health and safety concerns.

Many families are choosing to send their kids outside the district during key transitions, such as the beginning of middle and high school. About 41 percent of interdistrict transfers are requested in the high school years, with the largest number happening in ninth grade, the analysis showed.

Wilson notes the district loses its largest number of students in sixth grade, with many going to private schools.

KQED's map shows how many Oakland families requested to transfer for each school district. The data do not include how many were granted a transfer, but Wilson said about 80 to 90 percent of requests are approved.

Interdistrict Transfer Requests From Oakland to Other Districts, 2015-16

Data from the Oakland Unified School District. School names are as written in the application.

Lisa Pickoff-White/KQED

Berkeley Gets the Most Oakland Students

Oakland’s neighbors, including San Leandro, Alameda, Piedmont, San Francisco and Emeryville, get large chunks of Oakland students. Berkeley gets the most.

Over the last two years, the Berkeley Unified School District has accepted about 75 percent of all requests, said admissions manager Francisco Martinez. Most of those are for families who work for Berkeley Unified, he said. Last year, Berkeley had more than 700 interdistrict transfer students. Of those, about 40 percent were from Oakland.

School districts have some level of discretion for which students they accept. School boards in each district set those policies, and if interdistrict transfer students don’t maintain adequate eligibility, the district can send them back to the home district.

“If they are accepted, they have to have satisfactory grades, attendance and behavior,” Martinez said.

Coming Back to Oakland

As head of Oakland Unified enrollment, Wilson has made a few minor changes to the enrollment process to make families feel more welcome. But he said many families are still competing for a select few schools.

“The history of a school and a community lingers for many, many years even if the leadership and staff has changed and the culture has changed,” he said. “I don’t think the perceptions of quality about some of our secondary programs are really corroborated by what we’re really doing.”

As Claire was graduating from elementary school, her family applied to public, private and charter schools in both Oakland and San Francisco. But Claire is older now and she told her parents she wanted to go to school in Oakland.

This time around, Diamond says, she felt Oakland Unified was doing a better job educating kids. The family went on school visits and looked at classroom size, how long teachers and principals had been at the school and state test scores.

Her conclusion?

“The system is not broken, public schools are good, and diverse schools in diverse urban communities are good,” Diamond said.