Striking San Francisco teachers reached a deal with the district Friday, after leaving roughly 50,000 kids without an education for a week and their parents scrambling to figure out how to go to work without child care.

Teachers unions once again had put their own interests ahead of the children they’re supposed to serve.

School-choice programs can spare families of such hardships in the future.

By giving parents the power to vote with their feet, and their dollars, we can curb this cycle of strikes and hostage-taking once and for all.

The San Francisco teachers union demanded a 9% raise along with other benefits, even though their members are already pulling in an average salary of $103,472 per year — just in base pay.

That’s around the median individual income in San Francisco for a profession that only shows up to work 184 days a year.

Meanwhile, the district is staring down a $100 million deficit and is under state oversight due to a longstanding financial crisis.

The district provides about 6,000 teachers for 50,000 students — about one teacher for every eight kids, a ratio most private schools would envy.

Yet the union still wanted to hire more people. The goal was to pad their ranks, not help kids.

More hires mean more footsoldiers to push the union’s political pet projects and more dues-paying members to fatten its political war chest.

The union’s true colors showed in this strike: It even posted a picture showing a pro-teacher protester holding a sign from the “Party for Socialism and Liberation.”

It’s no secret that teachers unions have been behind protests against immigration enforcement, using their platforms to advance far-left agendas that have nothing to do with reading, writing or arithmetic.

Parents and students always get the short end of the stick in these power plays.

As one parent told the Associated Press, “If the strike continues, I’ll have to ask my job for a leave of absence, but it will affect me because if I don’t work, I don’t earn.”

That’s the human cost. Families are thrown into turmoil and kids are missing out on learning — all because the union decides to hold everyone hostage.

This mess stems from a fundamental flaw in public-sector unions: There’s no real pressure to perform or negotiate in good faith.

Families — the customers — can’t vote with their feet.

They’re stuck in their assigned district schools, no matter how dysfunctional.

The district doesn’t feel the pain either, because the money keeps rolling in from taxpayers regardless.

Only the families and taxpayers get screwed, over and over again.

Contrast that with the private sector: If baristas at Starbucks go on strike too often, you can switch to the coffee shop down the street.

Striking workers feel heat because they risk losing pay or even their jobs, and the employer feels the pain from lost business.

Everyone has skin in the game, which forces reasonable resolutions.

But in government monopoly education, there’s no such accountability. The unions can strike indefinitely, knowing families have nowhere else to go.

Even progressive icon Franklin D. Roosevelt understood the dangers of public sector unions.

In a 1937 letter to the president of the National Federation of Federal Employees, FDR wrote: “All Government employees should realize that the process of collective bargaining, as usually understood, cannot be transplanted into the public service. It has its distinct and insurmountable limitations when applied to public personnel management.”

He warned that strikes in the public sector are “unthinkable and intolerable” because they pit employees against the people they serve.

The good news is we have a way out: Gov. Gavin Newsom should immediately opt California into President Donald Trump’s new nationwide school-choice program.

As Colorado Gov. Jared Polis — a Democrat — put it, it’s a “no-brainer.”

This program would let families escape failing or strike-plagued districts, forcing schools to compete and improve.

Teachers who are fed up with the union’s antics can opt out, too, and keep their hard-earned paychecks.

It’s their right, and organizations like the Teacher Freedom Alliance offer free membership as an alternative, without the political baggage.

The best teachers would thrive even more by negotiating their own salaries directly with employers.

School choice means escaping strikes and putting power back in the hands of parents, prioritizing kids over special interests.

In San Francisco and across the country, it’s time to end the union stranglehold and let families choose.

The kids — and their futures — depend on it.

Corey DeAngelis is a senior fellow at Americans for Fair Treatment and a visiting fellow at the American Institute for Economic Research.