MOORESVILLE Sixty educators from across the nation roamed the halls and ringed the rooms of East Mooresville Intermediate School, searching for the secret formula. They found it in Erin Holsinger's fifth-grade math class.

There, a boy peering into his school-issued MacBook blitzed through fractions by himself, determined to reach sixth-grade work by winter. Three desks away, a girl was struggling with basic multiplication - only 29 percent right, her screen said - and Holsinger knelt beside her to assist. Curiosity was fed and embarrassment avoided, as teacher connected with student through emotion far more than Wi-Fi.

"This is not about the technology," Mark Edwards, superintendent of Mooresville Graded School District, would tell the visitors later over lunch. "It's not about the box. It's about changing the culture of instruction - preparing students for their future, not our past."

As debate continues over whether schools invest wisely in technology - and whether it measurably improves student achievement - Mooresville has quietly emerged as the de facto national model of the digital school.

Edwards spoke on a White House panel in September, and federal Department of Education officials often cite Mooresville as a symbolic success. Overwhelmed by requests to view the programs in action, the district now herds visitors into groups of 60 for monthly demonstrations; the waiting list stretches to April. What they are looking for is an explanation for the steady gains Mooresville has made since issuing laptops three years ago to 4,400 fourth through 12th-graders in five schools (three K-3 schools are not part of the program).

The district's graduation rate was 91 percent in 2011, up from 80 percent in 2008. On state tests in reading, math and science, an average of 88 percent of students across grades and subjects met proficiency standards, compared with 73 percent three years ago. Attendance is up, dropouts are down. Mooresville ranks 100th out of 115 districts in North Carolina in terms of dollars spent per student - $7,415.89 a year - but it is now third in test scores and second in graduation rates.

"Other districts are doing things, but what we see in Mooresville is the whole package: using the budget, innovating, using data, involvement with the community and leadership," said Karen Cator, a former Apple executive who is director of educational technology for the U.S. Department of Education. "There are lessons to be learned."

The numbers

Start with math lessons: Each student's MacBook Air is leased from Apple for $215 a year, including warranty, for a total of $1 million; an additional $100,000 a year goes for software. Terry Haas, the district's chief financial officer, said the money was freed up through "incredibly tough decisions."

Sixty-five jobs were eliminated, including 37 teachers, which resulted in larger class sizes - in middle schools, it is 30 instead of 18 - but district officials say they can be more efficiently managed because of the technology. Some costly items had become obsolete (like computer labs), though getting rid of others tested the willingness of teachers to embrace the new day: Who needs globes in the age of Google Earth?

Families pay $50 a year to subsidize computer repairs, though the fee is waived for those who cannot afford it, about 18 percent of them. Similarly, the district has negotiated a deal so that those without broadband Internet access can buy it for $9.99 a month.

Edwards said the technology had helped close racial performance gaps in a district where 27 percent of the students are minorities and 40 percent are poor enough to receive free or reduced-price lunches.

Others see broader economic benefits.

"Even in the downturn, we're a seller's market - people want to buy homes here," said Kent Temple, a real estate agent in town. "Families say, 'This is a chance for my child to compete with families that have more money than me.' Six years from now, you'll see how many from disadvantaged backgrounds go to college and make it."

Mooresville's laptops perform the same tasks as those in hundreds of other districts: They correct worksheets, assemble progress data for teachers, allow for compelling multimedia lessons, and let students work at their own pace or in groups, rather than all listening to one teacher. The difference, teachers and administrators here said, is they value computers not for the newest content they can deliver, but for how they tap into the oldest of student emotions - curiosity, boredom, embarrassment, angst - and help educators deliver what only people can.

Personalized education

Mooresville frequently tests students in various subjects to inform teachers where each needs help. Every quarter, department heads and principals present summary data to Edwards, who uses it to assess where teachers need improvement.

Special emphasis goes to identifying students who are only a few correct answers away from passing state proficiency standards. They are then told how close they are and, Edwards said, "You can, you can, you can."

In math, students used individualized software modules, with teachers stopping by occasionally to answer questions. ("It's like having a personal tutor," said Ethan Jones, the fifth-grader zooming toward sixth-grade material.) Teachers apportion their time based on the need of students, without the weaker ones having to struggle at the blackboard in front of the class; this dynamic has helped children with learning disabilities to participate and succeed in mainstream classes.

"There are students who might not have graduated five years ago who have graduated," said Melody Morrison, a case manager for Mooresville High School's special education programs. "They're not just our kids anymore. They're everybody's kids - all teachers throughout the school. The digital conversion has evened the playing field."

Trusting students

Many students adapted to the overhaul more easily than their teachers, some of whom resented having beloved tools - scripted lectures, printed textbooks and a predictable flow through the curriculum - vanish. The layoffs in 2009 and 2010, of about 10 percent of the district's teachers, helped weed out the most reluctant, Edwards said; others, he was able to convince that the technology would actually allow for more personal and enjoyable interaction with students.

"You have to trust kids more than you've ever trusted them," he said. "Your teachers have to be willing to give up control."

That was the primary concern that the 60 visitors expressed during their daylong sojourn to Mooresville in November. "I'm not sure our kids can be trusted the way these are," one teacher from the Midwest said, speaking on the condition of anonymity to avoid trouble back home.

Thomas Bertrand, superintendent of schools in Rochester, Ill., said he was struck by the "culture of collaboration among staff and kids" in Mooresville and would emphasize that as his district considered its own conversion.

"There's a tendency in teaching to try to control things, like a parent," said Scott Allen, a high school chemistry teacher in South Granville, N.C. "But I learn best at my own pace, and you have to realize that students learn best at their own pace, too."

Mooresville's tremendous focus on one data point - the percentage of students passing proficiency exams - has its pitfalls as well. At November's quarterly data meeting, there were kudos for several numbers whose rise or dip was not statistically significant, and no recognition that the students who passed by one or two questions could very well fail by one or two the next time around. Several colorful pie charts used metrics that were meaningless.

"I realize the fallacy of looking at one measure," Edwards said in an interview afterward. "We look at scholarships, A.P. courses taken, honors courses, SAT scores. But the measure that we use is what the state posts, and what parents look at when they're comparing schools moving here."