Lev Vygotsky, a Russian psychologist who thought play was the key to learning, died 72 years before the kindergartners at Powell Elementary School in Northwest Washington drew their first breath.

But his work could change their academic future and the direction of D.C. school reform. As students pair off to “buddy read,” act out chapters from storybooks and sit at their desks to write what they’ve learned, they are reinventing the classroom as Vygotsky saw it.

Schools Chancellor Kaya Henderson is placing a large bet on a curriculum called Tools of the Mind that is adapted from Vygotsky’s work. It uses carefully guided play to stimulate what neuroscientists call “executive function”: a combination of memory, impulse control, persistence and flexibility that researchers say may be an even more powerful determinant of educational success than IQ.

“This is a fundamental piece, one of the most significant things we can do,” Henderson said. At a cost of $1.5 million, she has taken Tools this year from a two-school pilot to 28 schools with 157 preschool, pre-K and kindergarten classes targeting disadvantaged students. If funding is available, she wants to add an additional 100 classes next year.

Tools also is crucial in Henderson’s attempt to shift priorities in the 45,000-student system. Her predecessor, Michelle A. Rhee, devoted much energy to school closings, teacher evaluations and revamping the bureaucracy. While such issues remain — another round of closings looms — Henderson said reform now must focus on “the hard, non-sexy work” of what and how children learn.

D.C. schools have rolled out the initial stages of a new curriculum, the city’s first in years, based on the Common Core State Standards. Those standards, adopted by the District and 40 states, provide a blueprint for what students should learn in English and math through 12th grade.

The curriculum, including Tools and other elements, offers a road map to teachers who have lamented a lack of guidance. Officials promise that students will be able to move from school to school without missing material or repeating it. This month, for example, first-graders citywide are — or are supposed to be — learning about dinosaurs.

Henderson hopes Tools of the Mind, compatible with the Common Core, will provide a foundation for changes ahead.

Vygotsky, who studied the role of culture and social interaction in child development, believed that play is the thing. Other early-childhood programs focus on play. But Tools is unique, experts say, because it uses play to build the capacity to “self-regulate,” or resist the impulses and distractions that can hinder academic growth.

This is a departure from the heavy emphasis on rote academic drills in other programs. Children in “Vygotskian” classrooms get the usual reading, phonics and math instruction. But embedded in their lessons are exercises designed to plant the seeds of self-control.

“It gets away from the notion that we have to do academics or play. It puts learning in a play context,” said Heather B. Weiss, founder and director of the Harvard Family Research Project, which studies early-childhood education.

Powell kindergarten teacher Sasha Otero begins the day with the children on the carpet. She introduces the “ike” sound. Otero draws a series of dashes on the board, one for every word in the sentence, “I like to bike and hike with Mike.”

Developers of Tools say the dashes serve as proxies for the words, helping kids break down the component sounds and stimulating short-term memory. Word by word, Otero leads them through the sentence and then asks what other “ike” words they can think of.

Instead of having them sit with hands raised, ready to blurt answers, Otero starts a short “turn and talk,” where they discuss “ike” words with their neighbors. Tools aims to avoid unregulated behavior by minimizing the time pupils spend in unstructured activities, like waiting for the teacher to call on them.

“You’re supposed to move at a fast pace and sweep the kids along,” said Otero, 23, who is two years out of Dartmouth College.

Down the hall in Laura Amling’s pre-K class, it’s time for “buddy reading,” where kids pair off on the carpet and take turns as reader and listener. To reinforce those roles, Amling hands each couple two cards. One shows an ear, the other a pair of lips.

Amling, 24, a third-year teacher, moves from pair to pair, listening in and observing. “Ask your friend what his favorite part is,” she said to one of the readers. The cards help kids get comfortable with defined roles and, again, self-regulation.

Students “plan” their play with Amling and her assistant, drawing or writing their intentions on half-sheets of paper (“Today I will . . .”). They disperse to centers of their choice, where they work with others. Last month, the centers were organized along a family and home theme, with a living room, bedroom, laundry room and other locations.

Among other objectives, Tools tries to dissolve traditional gender roles. Two boys are in the “laundry room,” pinning a small towel to a clothesline.

“Hey, Wilber! Remember, rub, rub, rub,” Amling calls out to another boy gently washing a doll in a bassinet. The play will become more elaborate, with students filling more complex roles. Later in the year, they will be customers and workers at supermarkets and restaurants. In kindergarten, they will act out stories from the “Magic Tree House” books, making their own props.

“People think that play is running around like maniacs. To us it’s a very serious thing,” said Deborah Leong, professor emerita of psychology at Metropolitan State College of Denver. She collaborated with a Russian emigre colleague, Elena Bodrova, who imported Vygotsky’s ideas to the United States and developed Tools in the early 1990s. Starting in Denver, Leong, Bodrova and their staff have trained teachers in 13 states who serve about 30,000 children. The District is the first school system in the Washington region to try Tools.

Leong said earlier generations came to school with many more hours of unstructured, unsupervised play under their belts. The experience, she believes, gave them a better grasp of how to work in groups and regulate selfish or destructive impulses.

Teachers have observed a rising tide of students with poor social skills. A national survey of 3,500 kindergarten teachers reported that 46 percent said at least half of their students had difficulty following directions.

There is relatively little rigorous research on the effectiveness of Tools. The U.S. Education Department’s What Works Clearinghouse said only one 2008 study met its evidence standards. The research, the department said, showed “no discernible effects in oral language, print knowledge, cognition or math.”

But Weiss and D.C. officials said the department’s analysis of that study is misleading because it doesn’t include social and emotional growth in the evaluation criteria. The study, which was conducted by W. Steven Barnett of Rutgers University and looked at poor 3- and 4-year-olds in New Jersey, showed Tools reduced negative behavior, which should help the children become better learners. Leong said other independent studies are in the pipeline.

D.C. officials said they also are guided by what they have observed.

“Tools classrooms hum,” said Miriam Calderon, former director of early-childhood education for the D.C. public schools and now a senior official at the U.S. Department of Health and Human Services. “Children are really acting on their own, engaging with the materials and engaging with the routine.”

Calderon took teachers and principals to visit New Jersey schools that use Tools. That led to the pilot last school year at Powell and Garfield Elementary.

Educators said they were struck by the results: more students reading at grade level, calmer classrooms, less teacher frustration.

“The academic growth of our Tools of the Mind students has been phenomenal,” Garfield Principal Angela Tilghman wrote in an e-mail. “Students’ vocabulary, [language] awareness and readiness for reading has skyrocketed. Watching students so intense, focused and self-directed is surely due to their self-regulation of behavior.” Officials also hope Tools will help prevent the misdiagnosis of learning disorders.

Otero and Powell Principal Janeece Docal beam as they watch 5-year-old David Salvador leave his “turn and talk” session, walk calmly to his desk with a small yellow bin of paper and pens and, along with other students, quietly begin to write.

“They’re owning the classroom,” Docal said.