SAN FRANCISCO » Three times over the past two years, school officials from Little Falls, Minn., have escaped the winter cold for two-day trips to Silicon Valley. Their destination: the headquarters of Apple.

In visits the officials described as inspirational, they checked out the company’s latest gadgets, discussed the instructional value of computers with high-level Apple executives and engineers, and dined with them and other educators at trendy restaurants. Apple paid for meals and their stay at a nearby inn.

The visits paid off for Apple too — to the tune of $1.2 million in sales. In September, Little Falls handed out iPads to 1,700 of its 2,500 students at a celebration in the school gym. And a few days earlier, 200 teachers got a pep talk via video chat from an Apple executive whom the school superintendent had come to know during his company visits.

"Both my visits there have been extraordinary," said Curt Tryggestad, superintendent of the Little Falls Community Schools, who visited Cupertino in 2010 and this year. "I was truly amazed to sit in a room with Apple vice presidents, people who were second in command to Steve Jobs."

The demand for technology in classrooms has given rise to a slick and fast-growing sales force. Makers of computers and other gear vigorously court educators as they vie for billions of dollars in school financing. They make pitches via email, make cold calls, arrange luncheons and hold community meetings, hoping to build relationships that could yield big contracts.

But Apple in particular woos the education market with a state-of-the art sales operation that educators say is unique, and that, public-interest watchdogs say, raises some concerns. Along with more traditional methods, Apple invites educators from around the country to small "executive briefings," which participants describe as equal parts conversation, seminar and backstage pass.

Such events might seem unremarkable in the business world, where closing a deal can involve thinly veiled junkets, golf outings and lavish dinners. But the courtship of public school officials entrusted with tax dollars is a more sensitive matter. Some critics say the trips could cast doubt on the impartiality of the officials’ buying decisions, which shape the way millions of students learn.

Mike Dean, a spokesman for Common Cause of Minnesota, a nonpartisan group that promotes open government, was critical of the Apple visits, calling them "influence peddling." He said he believed that a Minnesota law prohibiting government officials from accepting "anything of value" from contractors would apply to the hotel stay and dinners. And he said Apple was offering an experience that made potential buyers feel like insiders.

"There is a geek culture that very much worships Apple, and they’re feeding into that to get more contracts."

Apple declined to discuss the executive briefings. Natalie Kerris, a spokeswoman for the company, said education was "in its DNA." As to the public employees who participate in the trips, Kerris said: "We advise them to follow their local regulations."

Broadly, efforts by technology vendors to get close to educators are becoming more sophisticated, said John Richards, an adjunct lecturer at the Graduate School of Education at Harvard, where he teaches about education and technology.

"What the textbook sellers had perfected for years has moved into the high-tech world," said Richards, who also works as a consultant for technology companies in the education market.

The sales pitches come as questions persist about how effective high-tech products can be at improving student achievement. The companies say their products engage students and prepare them for a digital future, while some academics say technology is not fulfilling its promise.

Even Steve Jobs, Apple’s co-founder, turned skeptical about technology’s ability to improve education. In a new biography of Jobs, the book’s author, Walter Isaacson, describes a conversation this year between the ailing Jobs and Bill Gates, the Microsoft co-founder, in which the two men "agreed that computers had, so far, made surprisingly little impact on schools — far less than on other realms of society such as media and medicine and law."

The comments echo similar ones Jobs made in 1996, between his two stints at Apple.

In an interview with Wired magazine, Jobs said that "what’s wrong with education cannot be fixed with technology," even though he had himself "spearheaded giving away more computer equipment to schools than anybody else on the planet." Jobs blamed teachers’ unions for the decline in education.

Still, Jobs seemed to hold out hope that devices like the iPad could change things by replacing printed textbooks. Isaacson writes that the textbook market was the next big business Jobs hoped to disrupt with technology.

The executive briefings on Apple’s campus have been going on for more than a decade but have received little attention, partly because participants sign nondisclosure agreements that are meant to protect the company’s technical and business secrets.

Matt Mello, director of technology for the Holly Area Schools in Oakland County, Mich., went on a two-day trip to Apple headquarters in Cupertino, Calif., in April 2010, and his description of it is similar to those of other participants.

Mello chronicled his visit using the Moleskine notebook Apple gave him. On the first day, he said, there was a light breakfast at the hotel, a ride to Apple’s campus and a briefing around a U-shaped conference table that began with company executives asking the educators about their needs. The latest Apple laptops and other products were scattered around the room. They had lunch in the gourmet cafeteria, where Mello sampled a bit of everything, and he visited the company store.

"I joked that I felt like we were on hallowed ground," Mello said of the campus. "There’s this mystique."

Still, Mello said he was not sure what would come of a trip that had developed a few months earlier, when the regional sales representative for Apple "snuck a MacBook under my nose and got me to try it." Soon, he said, the district was conducting a test with 30 Apple laptops and considering whether to upgrade hundreds of Windows-based computers or switch to Apple.

Mello said the sales representative told him: "If you guys are serious, we could get you an invitation to an executive briefing in Cupertino."

The representative traveled to Cupertino for the meeting but hung in the background. The sales team wore ties, and the engineers and executives dressed casually. Sales pitches took a back seat to conversations and presentations about how students use computers.

One video showed a 10-year-old boy talking about creating podcasts with a MacBook.

The group met with a local participant in Apple’s "distinguished educator" program, Ted Lai, who talked about podcasting in schools. Then, in a room called the Jim Henson Studio, they learned to create podcasts using iMovie software. Soon, Mello was convinced.

"We went there with our eyes open but hesitant. What could be so compelling as to get us to move off our base? And they did it," Mello said.

What swayed him, he said, were the presentations but also the company’s bright new monitors: "We were looking at each other thinking, ‘Wow. I can’t believe these are available at this price point."’

Since then the district has switched to Apple, giving 350 laptops to teachers in 2010 and, this fall, 450 iPads and computers to high school students. The price: $637,000. Mello was joined on the trip by two principals, two assistant superintendents and a teacher. Apple paid for meals and a stay at the Inn at Saratoga, near the Apple campus, where rates run $189 for a single room that looks onto a tranquil creek. Airfare was not included. And the group did not let Apple pick up the drink tab at the hotel, Mello said, noting: "As a school district, we’re conscious of that sort of thing."

Rich Robinson, executive director of the Michigan Campaign Finance Network, a nonprofit watchdog group, said he did not believe the educators were violating state law. But he said the ethical issue seemed to be a gray area for public officials. "It’s acceptable business ethics," he said. "It’s not good public ethics."

For his part, Mello said he did not think the Apple perks had influenced him. But he said he believed that Apple, by inviting his district, which is relatively wealthy, was seeking to influence other Michigan schools. In fact, he said he was told as much by a senior sales executive during dinner at a Silicon Valley Latin American restaurant.

The executive even offered to throw in about $20,000 of wireless equipment, but the district declined because it had other plans, Mello said. Robinson and other watchdogs said state ethics rules were not uniform and varied widely. For instance, school officials in Nebraska, several of whom have visited Apple this year, are prohibited from accepting meals and hotels only if they agree to buy products in exchange, an overt quid pro quo which no one is suggesting is taking place.

In all, about 30 states have laws restricting gifts to state officials, laws that might invite scrutiny of Apple’s generosity, said Karen Hobert Flynn, vice president of state operations for Common Cause.

In Microsoft’s case, the company covers airfare, hotels and meals for participants in its events for teachers. It also invites administrators and school technology staff to regional meetings that are aimed at helping them solve technical issues. Because those meetings include people who can be involved in purchasing computers and other gear, Microsoft does not pay for travel or hotels.

And in the case of both the teacher meetings and the technical briefings, Microsoft requires that attendees bring a letter certifying that if they accept meals or any other perks, they will not be violating local, state or federal ethics laws, according to Kevin Hartley, associate general counsel at the company.

There is sensitivity about these issues on the educators’ side as well. In September, a group of state officials and educators in Idaho canceled a trip to Microsoft because they worried it might appear as if the trip had unfairly influenced any eventual purchase of Microsoft products.

Tryggestad from Little Falls said Apple did not push him to take anything that would violate state law, and that he did not think he or anyone in the district had done so.

When he went on his first visit to Apple in 2010, Tryggestad was joined by about a dozen other Minnesota superintendents. On his second visit this February, the group spent an afternoon at Stanford University talking to students and faculty who were experimenting with educational uses of technology.

In March, the district technology director visited Apple in a group that included his counterparts from schools in North Dakota, South Dakota, Nebraska and Kansas. Less than a month later, the Little Falls school board approved the big iPad purchase.