The Department of Education paid $350 million to boost broadband Internet access in city public schools — but only a handful of faculty and administrators say it was money well spent, according to a blistering new report from Comptroller Scott Stringer.

A survey of more than 400 teachers and principals found that only 10 percent were fully satisfied with the strength of the wireless signals on their campuses, Stringer said Sunday.

“If people cannot access broadband, that means those computers are not working in the classroom,” Stringer said. “It brings the entire system to a crashing halt.”

In addition, there is virtually no paper went, Stringer said.

“That’s [$350 million] for all schools. That’s what they could tell us.” said Marjorie Landa, deputy comptroller for audits.

“Tying that in to actual projects, plans, signatures, schools, oversight to make sure that the vendor wasn’t overbilling, that they were delivering what they were supposed to, that the right people were doing the work — no records for any of that.”

In addition to the 10 percent of survey respondents who said they were satisfied with their school’s Internet service, another 34 percent said they were somewhat satisfied.

That’s compared with 33 percent who said they were not satisfied and 20 percent who were somewhat dissatisfied. Three percent didn’t answer.

A Department of Education spokesperson spun the numbers in the school system’s favor, saying, “This report finds that every middle school already has high-speed Internet connections and that the majority of middle schools are satisfied with their Internet.”

But the DOE rep conceded the need for greater accountability, saying: “We also increased central oversight six years ago to manage technology projects in the best interest of students, schools, and taxpayers.”

Stringer, meanwhile, insisted that middle schools were the very ones that should be targeted for tech upgrades.

“We looked at middle school, and that is a very Internet-important age,” he said.

Additional reporting by Selim Algar