Hundreds of public schools have been teaching reading the wrong way for the last two decades, leaving an untold number of children struggling to acquire a crucial life skill, according to New York City’s schools chancellor.

Now, David C. Banks, the chancellor, wants to “sound the alarm” and is planning to force the nation’s largest school system to take a new approach.

On Tuesday, Mr. Banks will announce major changes to reading instruction in an aim to tackle a persistent problem: About half of city children in grades three through eight are not proficient in reading. Black, Latino and low-income children fare even worse.

In a recent interview, Mr. Banks said that the city’s approach had been “fundamentally flawed,” and had failed to follow the science of how students learn to read.

“It’s not your fault. It’s not your child’s fault. It was our fault,” Mr. Banks said. “This is the beginning of a massive turnaround.”

Over the next two years, the city’s 32 local school districts will adopt one of three curriculums selected by their superintendents. The curriculums use evidence-supported practices, including phonics — which teaches children how to decode letter sounds — and avoid strategies many reading experts say are flawed, like teaching children to use picture clues to guess words.

The move represents a sea change in a city where principals have historically retained authority over approaches to teaching at their individual schools.

Half of the districts will begin the program in September; the others will start in 2024. Waivers to opt out will only be considered for schools where more than 85 percent of students are proficient in reading, a threshold that only about 20 schools meet.

The nation’s biggest district joins a push to change reading

The move represents the most significant reading overhaul in New York City since the early 2000s, when some of the programs that the chancellor is now trying to uproot were first ushered in. It will immediately place the city at the forefront of a growing national movement to reform reading instruction.

Experts, lawmakers and families have pushed to abandon strategies that a mass of research shows do not work for all students and to embrace a set of practices known as the “science of reading.”

The stakes are clear: Children who cannot read well by third grade are at a disadvantage. They are more likely to drop out of high school, face incarceration and live in poverty as adults.

Still, curriculum reform is an enormous undertaking. The challenges are perhaps nowhere more apparent than in New York City, a sprawling system of some 700 elementary schools and a large population of disadvantaged children.

The city has been among the top markets for a beloved “balanced literacy” curriculum. The approach aims to nurture a passion for books, but has been criticized at times for including too little systematic instruction in core reading skills. Mr. Banks called the approach an “old way that has failed far too many kids.”

The new plan is backed by the teachers’ union, but has attracted immediate skepticism from some teachers, who often say major changes come with insufficient training. It has also drawn ire from the city’s principals’ union, which has called a uniform curricular approach “pedagogically unsound” in such a large system.

But New York City has never offered the “the right blueprint” on reading, Mr. Banks said. It has left teachers blamed for failures that were not their own, he said, and families without answers to what went wrong when their children fell behind.

As national reading scores have stagnated, nearly 20 states have prioritized phonics alongside work to expand student’s background knowledge, vocabulary and oral language skills, which research shows most children need to grasp how to decode words and understand what they read.

“I’m thrilled,” Susan Neuman, an early literacy development expert and a former U.S. assistant secretary for elementary and secondary education, said of the city’s plans.

“This is a bold effort,” she said. “And I think it’s very much the right way to go.”

Changing reading instruction will mean changing teachers

If New York City’s announcement is the starting line, a challenging road lies ahead.

Research shows that a new curriculum alone does not boost student outcomes. Major changes require teachers to reshape their existing practices and understanding of a subject through intensive training and coaching. Otherwise, they may lean on old instincts.

Even supporters of the plan admit that much can go wrong. Some worry that the other side of literacy — writing — needs more substantial attention. Or that unaddressed pandemic learning losses could hinder progress.

And addressing how elementary schools teach reading to younger students will not help older students who missed learning those skills.

The city will also need to overcome the frustrations of many school leaders over the plan’s rollout, as well as the fervent belief that some have in the programs they now use.

Hundreds of elementary schools in 2019 used a popular balanced literacy curriculum from Teachers College known as Units of Study, a report by two local news outlets, Chalkbeat and The City, shows. The curriculum has received failing marks from one major organization that rates program quality. But many school leaders value its attention to developing children’s passion for books, as well as its robust professional development offerings for teachers.

Several city principals have defended that curriculum publicly. Another Brooklyn principal, who spoke on condition of anonymity for fear of retribution, called the rollout demoralizing and said their school had seen good results from a modified version of Units of Study paired with a phonics program.

Henry Rubio, head of the principals’ union, said a recent survey showed that three of four school leaders were “dissatisfied” with the plan’s rollout.

“It’s the lack of respect for the community and school leader to get buy-in to make this work,” Mr. Rubio said. “What does that do to trust and morale?”

Schools will have a limited menu of reading curriculums

Under the plan, all school districts will adopt one of three curriculums that have received high marks from national curriculum review groups.

Carolyne Quintana, the deputy chancellor of teaching and learning, said officials weighed factors like text quality and accessibility for students, before narrowing down options with a small group of superintendents.

The three choices have some significant differences:

• Wit & Wisdom is known for its robust focus on knowledge building, which is important for helping students understand what they read. It does not cover foundational skills like phonics, and would therefore be paired with a phonics program like Fundations, which many schools already use. Baltimore schools, where about 60 percent of children are low-income, reported modest gains after adopting it.

• Expeditionary Learning has an explicit phonics program, and includes texts that draw from concepts in other subjects such as social studies and a more robust writing component. It also has significant amounts of extra teaching materials and guidance that schools may need additional help to absorb. The curriculum is used in Detroit, which has seen some progress since its rollout.

• Into Reading is the most traditional option, a “basal” program that uses texts written specifically to teach reading. Some teachers and principals have worried over a recent New York University report that found its content “likely reinforces stereotypes and portrays people of color in inferior and destructive ways.” Ms. Quintana said the company has assured officials it is “adamantly working on making revisions.”

Mr. Banks said he believes the changes will, ultimately, “make life easier for everyone.”

Many teachers spend long hours searching for — or even creating — materials to fill gaps in existing curriculum. And when children lack stable housing or change schools often for other reasons, it can be tougher to jump back in when classrooms use different approaches.

The chancellor has found one key ally in Michael Mulgrew, the president of the teacher’s union, who has long advocated a more uniform citywide approach. “We are supportive of this idea,” Mr. Mulgrew said.

“But there will be pessimism throughout schools,” he added.

Will it be the end of the reading wars?

The shift marks the latest — and what the chancellor says ought to be the last — major swing of the pendulum in the city’s reading instruction.

Twenty years ago, during the Bloomberg administration, Chancellor Joel Klein ushered in the era of balanced literacy at city schools, until a lack of progress led him to pilot other approaches. Years later, another chancellor, Carmen Fariña, a believer in independent reading time and having students choose their own books, again encouraged schools to adopt those strategies.

Richard Carranza called the city’s patchwork of practices unfeasible when he led the system, but his tenure overlapped with the first year of the pandemic and reading moved to the back burner.

Mr. Banks, and the mayor, Eric Adams, who has dyslexia, has said reading would be one of the top priorities for the administration. Already, Mr. Banks has required schools to adopt phonics programs and opened several new programs for students with dyslexia.

Teacher training on the new programs will begin this week and continue over the summer, and coaching will continue during the school year. The goal is for teachers to return in the fall with their first unit fully planned, officials said. Early childhood providers will also receive training in the coming months.

The first stage of rollout will include several areas where children have struggled most, such as Harlem (District 5), the northeast Bronx (12), East New York (19) Brownsville (23) and southeast Queens (32).

Sharon Roberts, a special education teacher at P.S. 9, the Walter Reed School in Queens, said she was “hopeful for the first time” in years.

Ms. Roberts said that it has long been left up to her “to fill the gap” and find materials that work for her students’ needs. But for the plan to be successful, she said teachers need to be “treated with respect again.”

“We’re tired of being blamed for so many things that are out of our reach,” she said.