Private institutions are attracting wealthy families who are frustrated with public schools' flip-flopping on remote and in-person learning.

Why it matters: The trend is weakening public schools, which will lose funding as they lose students, and deepening the divide between how rich and poor kids are educated.

What's happening: In districts across America, public schools have had to follow local and state guidelines and stick with online school, while private schools have offered in-person alternatives.

• That's appealing to parents who are fed up with virtual learning because it forces them to juggle work and child care, or because the schooling is not as high in quality as in-person instruction.

Just 5% of private schools were virtual this fall, according to survey data from the National Association of Independent Schools, cited by CNBC. Compare that with the 62% of public schoolkids who started the fall on Zoom, per Burbio, which has been tracking public school re-opening plans.

Private schools have a clear advantage in how they've been able to handle the pandemic:

• They were able to devise and advertise their reopening plans throughout the summer while public schools waited to hear from officials.
• They have the money to build tents for outdoor instruction or pay for testing to stay open even as cases rise.

And it's working. Private schools in several states have seen applications surge, reports the New York Times. And some of the country's biggest districts — like New York and Los Angeles — are losing thousands of students, per Axios' Oriana Gonzalez.

"The pandemic is an opportunity for privatization and you see people really feeding into that," says Jon Hale, a professor of education at the University of Illinois.

The stakes: Not only is this trend separating higher and lower income students, it's also widening the urban-rural divide.

• While 92% of people in urban areas live within five miles of a private school, only 34% of households in rural areas have a private option within the same radius, according to the Brookings Institution.

What we still don't know is whether parents will keep ditching public schools for private ones in 2021 and beyond.

• "I think once things get back to normal, most students will be returning," says Larry Ferlazzo, a public high school teacher in Sacramento.  "It's hard for me to imagine that a huge number of families are going to want to take the financial hit required to pay for private schools."
• Still, we may have already kickstarted a vicious cycle, says Hale. "Funding follows the students," he says. "Public schools are going to lose more money, and this is going to continue, if not get worse."