Hung on a building in the Connecticut town where 20 children and six adults were killed at an elementary school is a spray-painted sign with four words: “Hug a teacher today.”

It’s a testament to the teachers who sprang into action when a gunman broke into Sandy Hook Elementary School and opened fire. They hid students in closets and bathrooms, and even threw themselves in the line of fire. Some paid with their lives.

Their sacrifice was selfless and heroic, and most teachers say they would do exactly the same if they ever came face to face with a gunman in the classroom. At schools last week, many teachers got extra thanks from parents and students who were reminded in the aftermath of the Newtown, Conn., massacre of just how much they give.

“I really hope a lot of parents see teachers in a little bit of a different light about all that we do,” said Hal Krantz, a teacher at Coral Springs Middle School, about 20 miles north of Fort Lauderdale, Fla.

That gratitude for teachers is a respite from recent years in which politicians and the public have viewed them as anything but heroes. Instead, teachers have been the focus of increased scrutiny, criticized for what is perceived as having generous and unwarranted benefits and job security.

“I think a moment like this makes us appreciate and understand the degree to which we are dependent on our teachers to take care of our children in all kinds of ways, not just in what they learn in the classroom,” said Paula Fass, a history professor at the University of California, Berkeley.

Over the last four years, a wave of reforms, prompted largely by the U.S. Department of Education and its $4.35 billion Race to the Top competition, has led states to strip teachers of tenure and institute tougher evaluations based in considerable part on student scores on standardized tests. The heavier emphasis on testing has led to a narrowing of what is perceived as the teacher’s role in the classroom.

“Most of the talk about teachers lately has been, ‘Should we judge teachers simply by children’s performance on standardized tests?'” said Patricia Albjerg Graham, a professor of the history of education at Harvard University. “And while it’s very important that teachers assist children in learning, it’s also true that they help them get in the mood for learning and protect them and care for them while they’re in school.”

Graham began teaching at a rural school in southern Virginia in 1955 and said even then teachers viewed protecting students as part of their job. During the Cold War, teachers led students through drills in the event of a nuclear bomb attack. Today, they lead them through the halls on fire drills and even have to take threats like shootings into account.

“I’m certainly proud of those teachers that lost their lives or got injured,” Krantz said. “It always makes you feel proud to be part of that whole society.”

While teachers in the United States have seen their responsibilities increase, their salaries have remained relatively flat — at about $55,000 after adjustment for inflation — over the last two decades, and salaries for starting teachers are usually lower. And while teachers in countries that outperform U.S. students on international tests tend to be held in the highest esteem, in the U.S., teaching is often derided as a job of last resort.

President Obama addressed the need to elevate the status of teachers in his State of the Union address last year.

“In South Korea, teachers are known as ‘nation builders,'” he said. “Here in America, it’s time we treated the people who educate our children with the same level of respect.”

His next line, however, suggested not all merited that status: “We want to reward good teachers and stop making excuses for bad ones.”

Parents may like their own child’s teacher, but their overall confidence in U.S. schools appears to have reached a low point. A Gallup poll released earlier this year found that just 29 percent had a “great deal” or “quite a lot” of confidence in public schools — the lowest level in nearly four decades.

“I think there has been a fairly concerted attack on teachers and teaching, specifically focusing on unionized teachers,” said Jeffrey Mirel, an education professor at the University of Michigan.

Indeed, much of the criticism about education in the United States has centered on teachers and firing or weakening their benefits as part of the solution. When a board of trustees needed to come up with ways to improve one of the state’s worst-performing schools in 2010, it decided to fire all of the teachers there — a decision that Obama said was an example of why accountability is needed in the most troubled schools.

The teachers were eventually allowed to keep their jobs, but in some ways the damage had already been done.

Whether the courageous actions in Newtown, Conn., lead to anything more than a temporary shift in the tone of how the nation talks about teachers remains to be seen.

But for the moment, teachers are grateful.

“When situations like that occur, teachers basically have a disregard for their own safety and put their own bodies between whatever might be happening to keep their kids safe,” Krantz said. “I think we’re always conscious of the fact that something like that could really happen.”