Anybody used to sitting through public comment at Board of Supervisors meetings knows the vent sessions are usually mind-numbing affairs requiring a lot of caffeine and even more patience.

That certainly wasn’t the case Wednesday night as scores of teachers lined up to speak for hours about the devastation being wrought on their profession in San Francisco. The stories were riveting and heart-wrenching. Two-, three- and even five-hour daily commutes. Paying 75 percent of their salary for a studio apartment for their family of three. The “lucky” ones who have their own in-law units without kitchens.

Working two or three side jobs to make rent. Couch-surfing with other teachers after an eviction. Seeing multiple colleagues from their schools leave every year for better salaries and cheaper rent elsewhere. Wondering how much longer they can remain in the job they love.

Supervisors Hillary Ronen and Ahsha Safai — both parents of young children — called a hearing to suss out why it’s taken so long for the school district and city to make any progress when it comes to housing teachers. A Chronicle investigation last year showed the average pay for public school teachers in San Francisco ranks No. 528 among 821 school districts in California, despite the city having the highest cost of housing in the state.

As I wrote last month, building teacher housing has been discussed in San Francisco for 13 years — and still no site has been selected, no decisions have been made about how the apartments will be doled out, and financing has not been determined. But other than that, the district’s really onto something.

Olson Lee, director of the mayor’s office of housing, said that a site for teacher housing will be picked this summer and that a request for proposals to develop it will be ready by the end of the year. He said it will probably take four more years for the first families to move in. That means teacher housing still won’t be a reality in San Francisco until 2022 at the earliest.

It turns out teacher housing has been discussed in San Francisco since the late 1990s, when there was actually — hold onto your seats — a real plan. The nation’s first publicly subsidized teacher housing was due to open next to Dianne Feinstein Elementary in the Sunset in partnership with the U.S. Department of Housing and Urban Development.

The 43 units were set to open in 2002, but neighbors and then-Supervisor Leland Yee killed the project. After pleading guilty to felony racketeering, Yee now lives in publicly funded housing: federal prison. The teachers still have nothing. Just saying.

Demonstrating why it’s important that the board now has mothers on it for the first time since 2010, Ronen and Supervisor Sandra Lee Fewer got visibly worked up over the city and school district’s incredibly slow movement on the issue. It’s like the excruciating wait for your kid to tie his shoes in the morning — if he were a highly paid professional and the fate of the city’s school system depended on it.

School board member Mark Sanchez described the pace well. “I’d say it’s glacial, but I think with global warming, it’s slower than glacial,” he said.

In 2015, city and school district officials set a goal of helping 500 teachers find stable housing within five years through a multipronged approach of building teacher housing, staving off eviction, and offering rental and down-payment loan assistance. Ronen pressed them on how many teachers they’ve helped since then. The stunning answer? Sixteen. “It’s mind-boggling,” Ronen said.

Fewer had harsh words for city staff, and I hope Mayor Ed Lee, who was not present, got the message.

“We have lost our way as a city,” she said. “This idea of build, build, build? I’m just going to tell educators in this room: Do not believe the hype. Eighty percent that is being built is not for you. You cannot afford it.”

Teachers were clearly pleased that somebody — anybody — in power was finally understanding their totally unsustainable lifestyles.

Vidya Karra, 33, is a coach for other teachers at San Francisco Public Montessori, an elementary school in Pacific Heights. She’s been teaching for eight years and has a master’s degree from UCLA.

She has several side jobs within the school district, including coaching teachers on weekends who are about to take big tests and going to the homes of children who are too chronically ill to attend school. Just recently, she lost one of those young students, a 3-year-old in the district’s pre-K program, to stomach cancer.

If that job isn’t worth a one-bedroom apartment of her own, I don’t know what is. But she can’t afford one, and she’s considering moving home to Dallas.

“It’s painful, the anxiety,” she said through tears. “I’m in my 30s, and I’m living paycheck to paycheck. I don’t want to have five roommates. I’ve paid my dues.”

She was hopeful when she found a listing for a Sunset studio at $1,800 a month — her maximum — but found when she visited that it had no kitchen.

A new report from Harvey Rose, the board’s legislative and budget analyst, found Karra’s experience normal. No teacher makes enough to comfortably afford a studio or one-bedroom in the city, he found. Even a teacher with a bachelor’s degree and more than 25 years of experience makes $6,000 too little to afford a studio apartment.

Susan Kitchell is in that boat. She’s a 64-year-old nurse at Galileo High and must be out of her two-bedroom apartment in the Richmond by August after losing a court fight over an Ellis Act eviction. The apartment is where she brought her now-adult son home after he was born, where they celebrated his acceptance to college and where they mourned the death of his dad.

“The feasibility of staying here is slim to none,” she said. “But you can’t have a city without teachers.”

Is that statement true? I’d say so, but San Francisco may soon find out for sure.

San Francisco Chronicle columnist Heather Knight appears Tuesdays and Fridays. Email: hknight@sfchronicle.com Twitter: @hknightsf