This article is part of our Learning special report about how the pandemic has continued to change how we approach education.

RICHMOND, Va. — The student in Cassie Gilboy’s first-grade class stumbled over the word ‘pig.’ Instead of looking at a picture for clues, she tapped out the sound of each letter with her fingers to break the word apart—/p/ /i/ /g/. She then exclaimed “pig” with a big smile.

This fall, the students at Broad Rock Elementary School in Richmond are learning to read using their fingers to break down words sound by sound and mirrors to watch how their mouths move when they say specific letters.

The central Virginia school district is placing a big bet on an evidence-based approach to teaching children to read, one that many districts and states are embracing this fall. The approach, known as the “science of reading,” relies on helping students decode the words on the page by understanding the sounds that letters make.

For the moment, at least, this is the method that researchers, educators and classroom teachers, especially, seem to agree on. After several decades of so-called reading wars, where dubious theories led educators to abandon the phonics method in favor of a variety of divergent — and often unsuccessful — literacy learning techniques, a growing number of states and districts are right back where they started. And there seems to be growing consensus, and evidence, that this is a solid path to improving literacy at an early age.

Researchers identified the need to focus on phonics and phonemic awareness as early as the 1950s. Nevertheless, the education field shifted to other curriculums in recent years, which has been linked to a crisis in early literacy, with barely a third of students nationwide mastering reading by fourth grade.

Remote learning and missed school days during the pandemic have only made the problem worse, with the biggest drop in reading scores for 9-year-olds in 30 years, new national data shows. But the pandemic also brought billions in federal Covid relief aid to school districts, allowing Richmond and others to accelerate the adoption of evidence-based curriculum and training.

“If we can get this right, our kids go to third grade as strong readers, which allows them to go into middle school ready for whatever,” said Tyra Harrison, executive director of teaching and learning at Richmond Public Schools. “It really is about what we are trying to accomplish with kids.”

Nineteen states have passed legislation requiring this sort of evidence-based reading instruction, including Tennessee, Alabama and North Carolina, with many more districts, like Richmond, using the extra federal dollars to overhaul their reading curriculum and train teachers.

Mississippi, the first state to pass legislation in 2013, saw its fourth-grade reading scores jump strikingly over the past decade, moving the state to 29th in the nation by 2019, from 49th in 2013. North Carolina, which has trained thousands of teachers on the instructional approach, recently released scores showing students in the primary grades made gains greater in reading proficiency than those in other states.

Still, many districts continue to teach what’s known as balanced literacy, which relies heavily on a technique known as “cuing,” which encourages students to guess unfamiliar words based on context or pictures rather than learn the underlying structure of words.

“Once you do that, you put decoding in the back seat and students don’t learn how to crack the code of language,” diminishing their reading skills, said Sue Pimentel, co-founder of StandardsWork and one of the nation’s top K-12 literacy experts.

The other weakness of such literacy programs, experts say, is assigning texts based on a student’s reading level rather than exposing them to challenging, grade-level books that build knowledge and vocabulary in a range of subjects.

“There’s no real knowledge-building going on,” Ms. Pimentel said, “which keeps them behind.”

Critics of the science of reading deride the approach as “drill and kill,” boring children with an exclusive focus on foundational skills, a concern that Ms. Pimentel and others reject. That’s where good teachers come in, said Claude Goldenberg, an emeritus education professor at Stanford.

“We need to help train, mentor and monitor teachers to help them do it in a way that’s effective,” he said.

Richmond Public Schools, a district where nearly 40 percent of first graders were identified as needing reading intervention in the spring before the pandemic — a rate almost twice that of Virginia as a whole — has started an ambitious five-year literacy initiative to get all students reading at or above grade level in third grade.

The district is taking a “systems approach to building a culture of literacy,” said Eboni Massey, manager of literacy across the district, that begins with the science of reading, but extends beyond the foundational skills. The district’s Lit Limo gave out more than 35,000 books to children over the last few years, and its book vending machines allow students to earn coins to buy books.

Teachers also incorporate other components of reading — vocabulary, comprehension and knowledge building — into their lessons.

But the core of the new initiative is the science of reading. “The difference between what we’ve been doing historically and what we’re doing now is that this is based on research,” Ms. Harrison said. “They’re proven to work for children.”

That includes Language Essentials for Teachers of Reading and Spelling, referred to as L.E.T.R.S., one of the most frequently used professional development options for effective literacy instruction. The program is intensive and costly, taking about 160 hours over two years to complete. But it teaches crucial concepts about language and the brain that can change how educators think about reading instruction.

For Ms. Gilboy, the new instructional approach enables all her first graders to be successful, particularly the 70 percent who are still learning to speak English.

“They can’t guess a word that they don’t know, but they can sound it out and then later apply the vocabulary,” she said. “With the science of reading every kid can be a reader. It really levels the playing field.”

During small group sessions, her students are using hands-on techniques with magnets, cubes, play dough or just their fingers to practice tapping out words.

Sometimes lessons will focus on specific sounds, and students will use mirrors to watch how their mouths move when pronouncing the sound and feel how different sounds vibrate their noses or vocal cords. Spelling, a favorite among Ms. Gilboy’s students, involves them segmenting words by their sounds and putting them back together. All these skills build upon each other, and lessons typically end with a decodable text.

After just one year using the new reading strategy, Richmond Public Schools raised its early literacy scores by seven points, the largest single-year gains the district has seen. If they continue their current trajectory, district leaders expect to close the reading gap between Richmond and the rest of the state.

“If we’re able to maintain the path that we’re on, I would predict probably in the next three to five years, we would be able to see those gaps closed,” Ms. Massey said.

Ms. Harrison was even more optimistic. “I’m going to say two.”

Bella DiMarco is a policy analyst for FutureEd, a think tank at Georgetown University’s McCourt School of Public Policy. Phyllis W. Jordan, associate director of FutureEd, contributed to this report.