It’s been a terrible season for the Westside Waves, but not because of anything that happened on the soccer field.

The girls, ages 12 to 14, were supposed to spend their spring season having fun, kicking the ball around, trying to beat their competitors. Together since third grade, they were supposed to play one last season before many head to high school in the fall. They were supposed to be whole.

But instead, the season has been about making get-well cards that didn’t work. About the shock and grief of losing one of their teammates, 14-year-old Madlen Koteva, to San Francisco’s deadly streets. About attending her funeral in their matching teal jerseys and bravely walking past her open casket to say goodbye.

About demanding City Hall make long-overdue, simple improvements to its streets so that no other group of friends has to lose a beloved member of its pack.

“It shouldn’t take our friend to die to fix this problem,” said Leela Sriram, 14, a classmate at A.P. Giannini Middle School in the Outer Sunset.

Leela and her teammates sat in a half circle at the soccer fields near A.P. Giannini the other day, all braces and ponytails and knee socks. They talked about Madlen, sharing their rapid-fire memories in unison, their voices blending together as one.

She was in my homeroom. She was in my drama class. We had the same social studies teacher. She was super smart. She was up on pop culture. All of her pencils were pink. She was very happy. She said hi to everyone. She was funny. She never seemed to have a bad day.

Madlen, a native of Bulgaria who moved to San Francisco while in elementary school, was one of 12 people to die in San Francisco traffic in the first four months of this year. If that pace holds, the city will tally 36 traffic fatalities in 2019.

That would be the highest on record since Vision Zero began five years ago. The program set a target of eliminating all traffic deaths in the city within a decade. But halfway through, San Francisco is nowhere near achieving that goal. And considering the city’s reactive, piecemeal approach to improving streets over the past five years, it might as well be called Zero Vision.

“What we’re doing is not working, this street-by-street approach,” said Jodie Medeiros, executive director of Walk San Francisco, the pedestrian advocacy nonprofit. “We really need to look at transformative policies to change what we’re doing.”

The city’s strategy has centered on looking at each bike lane or intersection where somebody has died and trying to make it safer. But those obvious fixes — building protected bike lanes, removing parking spaces at intersections so drivers can see pedestrians entering crosswalks, installing speed humps — should happen now. All over the city. To prevent deaths rather than fix a problem after someone is killed.

A spokeswoman for the San Francisco Municipal Transportation Agency said it has made safety improvements on 40 miles of streets in the past three years. But there are more than 1,200 miles of streets in the city.

If simple changes had been made to John Muir Drive alongside Lake Merced — the same road where another pedestrian, 50-year-old Galina Tuchfeld, was struck by a car and killed in 2015 — maybe Madlen would still be playing soccer.

She always tried her hardest. She took it so seriously. She was really fast. She really enjoyed being part of the team.

“Oh my God, she was a joy, just a joy. A happy bundle of hardworking joy,” said Annie Murphy, the team’s coach. She said Madlen was strong and tall, but refused to play too aggressively because she didn’t want to hurt her opponents.

The eighth-grader went to an after-school dance on Friday, March 15 — there was free boba tea and $1 pizza slices. That was the day the school district mailed letters to students telling them which school they’d been assigned to for the fall. Madlen had hoped for Lowell High, but she never found out.

That evening, she and her mother walked in a crosswalk near their home. At 6:16 p.m., everything changed. For Madlen. For her family. And for the Westside Waves.

A 91-year-old driver, Margie Brady of San Francisco, hit Madlen, reportedly telling police the sun’s glare made her hard to see. Her mother was injured but survived. Police cited Brady on May 1 for vehicular manslaughter and failure to yield to a pedestrian in a crosswalk.

An ambulance rushed Madlen to San Francisco General Hospital, where doctors placed her in a medically induced coma. The Westside Waves weren’t allowed to visit their teammate in the intensive care unit, so they skipped their next practice to make get-well cards.

School let out for spring break the last week of March, and the girls fanned out to various vacation spots. But the fun was short lived. Doctors determined Madlen was brain dead, and her parents took her off life support on March 25.

“I found out when someone texted me,” said 12-year-old Malea Smith. “She asked me if I heard about Madlen, and I said no. And she said she passed away.”

Others learned via Instagram. One girl read the post five times. It didn’t feel real.

“I don’t think any of us at our age had ever lost someone and not had the chance to say goodbye,” said Maureen Loftus, who is 14.

The girls wore their jerseys to Madlen’s April 2 funeral at a Russian Orthodox church on Geary Boulevard. They stood together, holding candles, before filing past Madlen’s body, visible in an open casket. She was buried in a pink shirt beside teddy bears. To see a girl with so much life drained of it upset them.

It was very weird. She looked empty. Hollow. No expression. She looked like a stranger. Like a doll. I thought the only way I could say goodbye is if I saw her. I don’t know how her parents were able to stand there next to her, next to her dead body.

“We were all very sad,” said 13-year-old Natalie Ogden, adding that reassurances from Madlen’s dad helped — that his girl was in heaven and not there in that box. “He said she’s smiling and laughing and happy.”

The girls kept playing soccer, but their hearts haven’t fully been in it. They’re tired, they said. They wear black armbands with Madlen’s number, 11, to every game. The skinnier girls have to wear the armbands on their legs so they don’t fall off.

On April 17, the girls met at the bottom of City Hall’s big marble staircase to deliver a letter to the mayor and every supervisor.

Why, they wanted to know, hadn’t the curbs leading to the crosswalks on John Muir Drive been painted red and parking spaces removed, so drivers and pedestrians could see each other better? Why hadn’t flashing pedestrian crossing signs been installed? Why was the speed limit 30 mph instead of 25? After all, there are homes right there.

“These are all obvious and easily achieved improvements to us middle schoolers,” read the letter, signed by each Westside Wave in looping cursive.

The problem is the city, once described by a supervisor as like steering a tanker through ice, moves at a speed far outpaced by whizzing street traffic. Erica Kato, a spokeswoman for the SFMTA, said the agency plans to remove parking spaces near three crosswalks on John Muir and to raise the crosswalks so they’re easier to see.

She added the agency will accelerate the pace of its safety improvements under direction from Mayor London Breed.

Supervisor Norman Yee, who represents Madlen’s district and was seriously injured by a car years ago, is preparing legislation mandating “daylighting” — removing parking spaces at intersections — around the city. He also wants speed limits reduced in residential neighborhoods to 20 mph, more money for traffic officers, and state approval to ticket speeders recorded by automated cameras.

All of this should happen. And if you value a parking space or the ability to zip through residential neighborhoods more than a human life, your priorities are simply out of whack.

The Westside Waves are now more cautious walking the city’s streets, and they’re angry that the only thing that’s changed at the crosswalk where Madlen was hit seven weeks ago is the installation of a sign that flashes cars’ speeds as they whisk past. Well, that and flowers left in memoriam, now withered.

“The process of saving lives shouldn’t have to take so much bureaucracy,” Maureen said.

They need to start making changes faster. The cars go really fast, and it’s hard to see. Our parents say we can’t walk around on our own. We should be able to walk the streets safely.

The girls’ conversation wound down. They stood in a circle with their coach, putting their right hands in the center.

“One, two, three, Waves!” the girls called out, raising their hands in the air joyfully.

The team left the field, kicking their soccer balls. All but one.

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