WASHINGTON — Republican leaders, turning away from significant gun control legislation, have shifted instead toward measures that would beef up security at the nation’s schools, hoping the push will quell public uproar over the recent massacre in Parkland, Fla.

But as students and parents from Marjory Stoneman Douglas High School continue their own organizing, the school safety strategy is unlikely to end the debate. Democrats and gun control advocates accused Republicans and the National Rifle Association of using school safety to divert attention from what they see as the real issue: the proliferation of guns that have been used in mass shootings at concerts, in movie theaters, on college campuses, in churches and at workplaces, as well as at public schools.

“This time, the gun rights crowd messed with the wrong community, the wrong kids and the wrong dad,” said Fred Guttenberg, whose 14-year-old daughter, Jaime, was killed at the school. He added, “I intend to be a part of breaking this gun lobby.”

The Republican-controlled House plans to vote next week on the STOP School Violence Act, a bill that would authorize $50 million annually for safety improvements, including training teachers and students in how to prevent violence and developing anonymous reporting systems for threats of school violence.

The bill, drafted by Representative John Rutherford, a Republican and former sheriff from Jacksonville, Fla., is one of a flurry of bipartisan measures introduced in the House and the Senate devoted to school safety — without curbs on guns. In the Senate, a companion bill would also give schools money for physical improvements, such as installing metal detectors or bulletproof doors.

And Senator Lamar Alexander of Tennessee, the chairman of the Senate education committee, introduced his own school safety measure on Wednesday. His bill would allow 100,000 public schools to use federal dollars for school counselors, alarm systems, security cameras and crisis intervention training.

Education Secretary Betsy DeVos threw her weight behind what she said was the only approach that could muster broad support after a brief but contentious visit on Wednesday to Stoneman Douglas High School, where 17 students and faculty were gunned down on Valentine’s Day.

“I think there’s an opportunity to take some practical steps that many, many people agree on and continue pushing forward on things that have broad support,” she said.

But as the midterm election season begins, the school safety votes may only be an opening volley.

“The Republicans would like to have the public think they’re doing something and have the N.R.A. think they’re doing nothing,” said Representative Steny H. Hoyer of Maryland, the No. 2 Democrat in the House.

Gun control has long been one of the most divisive and contentious issues in Washington, and the rush to legislate on school safety reflects the difficulty of passing measures that have anything to do with guns. On Wednesday, students advocating gun safety legislation staged a sit-in outside the office of Senator Mitch McConnell of Kentucky, the Republican leader, chanting “Enough is enough!” and “Not one more!” Eight were arrested, police said.

But most gun safety proposals — including expanding background checks for gun purchases, raising the minimum age for buying rifles to 21 from 18, banning assault-style weapons like the AR-15 used by the gunman in Parkland and taking guns away from people deemed mentally unfit — appear to be going nowhere on Capitol Hill. President Trump’s mercurial statements have not helped. At a televised White House session, he appeared to back broad gun control legislation, only to muddy his position after an evening meeting with the N.R.A.’s chief lobbyist.

One exception is the Fix NICS Act, a modest measure that would offer incentives to states and federal agencies to improve reporting to the National Instant Criminal Background Check System, or NICS, for gun purchasers. The measure, which is backed by the N.R.A., has already passed the House and has broad bipartisan support in the Senate.

But even that legislation is facing a hurdle: Mr. McConnell cannot bring it up quickly for a vote because Senate rules require unanimous consent to do so, and at least one senator, Mike Lee, Republican of Utah, has objected. And while Mr. McConnell is a co-sponsor of the Senate’s version of the STOP School Violence Act, he has not said when the Senate will consider it.

The Senate’s chief sponsor of the STOP School Violence Act, Senator Orrin G. Hatch, Republican of Utah, said in an interview Wednesday that his aim was to focus on “special programs and special approaches toward making these schools safer and more acceptable to the families and kids.”

As for Democrats who consider the measure insufficient, Mr. Hatch said: “That’s their motif every time. I mean, they know that if they can raise hell against guns and so forth, that that gives them a lot of publicity. But that doesn’t necessarily help us in our educational processes.”

Senator Christopher S. Murphy, Democrat of Connecticut and a co-sponsor of Mr. Hatch’s bill, said he did not want the Senate to lose sight of more far-reaching legislation that would address gun violence head-on.

“That’s a useful bill, but it doesn’t have anything to do with gun laws,” Mr. Murphy said. “Anybody whose only solution to the school shooting epidemic is to make our schools fortresses doesn’t understand the root of this problem.”

Randi Weingarten, the president of the American Federation of Teachers, also welcomed efforts to increase safety measures and resources, but she said legislators and Mr. Trump had used it deflect from the larger demands of the public, including students at Marjory Stoneman Douglas, who had been in the forefront of gun control advocacy since the shooting.

“The kids from Stoneman Douglas said, ‘Do certain common-sense, gun violence reduction measures — don’t change the subject,’” Ms. Weingarten said.

While Republicans were talking about school safety, Senate Democrats on Thursday sought to keep the focus on guns. Senators Debbie Stabenow of Michigan, and Bill Nelson of Florida, convened a Democrats-only afternoon hearing to take testimony from those affected by gun violence.

Among the witnesses were Mr. Guttenberg and David Hogg, a 17-year-old Stoneman Douglas senior who has become a vocal national spokesman for gun control.

In Parkland on Wednesday, Ms. DeVos was greeted less than enthusiastically by many students, who took to social media to complain that she did not have any substantive interactions with them. (Dwyane Wade, a basketball star for the Miami Heat who visited after Ms. DeVos, got a much warmer reception.)

“I thought she would at least give us her ‘thoughts and prayers,’ but she refused to even meet/speak with students. I don’t understand the point of her being here,” tweeted Carly Novell, editor of the student newspaper, The Eagle Eye, which covered the secretary’s visit.

Another student, Aly Sheehy, tweeted, “Do something unexpected: answer our questions.”