TALLAHASSEE, Fla. – Pledging “change is coming” and “never again,” Gov. Rick Scott and Republican legislative leaders on Friday released proposals encompassing gun laws, safer schools and mental health, with the goal of preventing future tragedies like last week’s mass shooting at a Broward County high school that left 14 students and three faculty members dead.

The plans came nine days after 19-year-old Nikolas Cruz went on a shooting spree at Marjory Stoneman Douglas High School in Parkland. Cruz has been charged with 17 counts of premeditated murder in the school deaths.

Among Scott's top plans were to require at least one sworn police officer in each of Florida's 4,000 public schools and raising the minimum age to buy a gun to 21.

Scott is proposing spending $500 million on school safety improvements and keeping guns away from individuals struggling with mental illness.

The governor said the ideas grew out of emergency meetings he held earlier this week with law enforcement officials, school administrators, teachers, mental health experts and state agency leadership, as well as meetings with students at the Parkland school.

"I want to make it virtually impossible for anyone who has mental issues to use a gun. I want to make it virtually impossible for anyone who is a danger to themselves or others to use a gun," Scott said. "Let's take a moment to look at the case of this killer. This person was not stopped from legally purchasing a weapon, was not arrested, was not detained, and was never forced to turn in his weapons."

ACTION PLAN: Bullet points of Gov. Scott's plan

READ: Governor's remarks as prepared for delivery

WATCH: Gov. Scott announces plan

Scott wants to strengthen restrictions on people committed for mental examination under Florida's Baker Act from buying and possessing guns and ban anyone under an injunction for stalking, domestic or sexual violence. He also wants to create a "violent threat restraining order," which will allow a court to prohibit a violent or mentally ill person from buying or possessing a gun or any other weapon when a family member, welfare expert or law enforcement officer files a sworn request involving a threat of violence.

While Scott stopped short of banning any particular weapons, he is asking for the age to buy any gun be raised to 21, with exceptions for military members and their spouses and law enforcement, and a ban on bump stocks, which make a semiautomatic rifle fire more rapidly.

The sweeping plans -- which total up to $500 million -- swiftly drew the ire of Democrats, who said the measures don’t go far enough, and National Rifle Association lobbyist Marion Hammer, who blasted the proposals as punishing gun owners for the crimes of a madman.

Scott balked at the idea of armed teachers, saying “my focus is on bringing in law enforcement.”

Mental health changes

Scott called for $50 million specifically for mental health initiatives, including expanding mental health teams across the state available for counseling, crisis management and other mental health service and adding 67 additional crisis welfare workers at the Florida Department of Children and Families by July 15.

The last part of Scott's plan was specifically about protecting students, which includes school-hardening measures like metal detectors, bulletproof glass, steel doors and upgraded locks. He wants all school districts to meet minimum school safety and security standards by July 1.

He called not only for a sworn officer or sheriff's deputy at every public school, he wants to have one armed officer for every 1,000 students, so large schools would have multiple officers on campus by the time schools open next August.

"But let me be clear, there is nothing more important than the safety of our children," Scott said. "Our kids deserve nothing less. Fortunately, our economy is booming, and we have the resources to protect our schools and our students. And, if providing this funding means we won't be able to cut taxes this year, so be it."

Florida Sen. Bill Nelson, who is expecting Scott to challenge him for re-election this fall, said the governor's plan falls short.

"Students, parents and teachers across our state are demanding action, but instead of listening to them, it's clear the governor is once again choosing to listen only to the NRA," Nelson said in a statement. "The governor's plan doesn't do one thing to ensure comprehensive criminal background checks or ban assault rifles, like the AR-15. We need to get these assault rifles off our streets and expand criminal background checks for anyone acquiring a gun."

But Scott rejected “a mass takeaway of Second Amendment rights.”

“That is not the answer. Keeping guns away from dangerous people, and people with mental illness, is what we need to do,” he said.

News4Jax political analyst Rick Mullaney, director of Jacksonville University's Public Policy Institute, said the governor avoided the big issue of an all-out ban on assault rifles but made key points.

"My general impression is that it's both good policy and good politics," Mullaney said. "The reason I think it's good politics is that I do believe that you are seeing this very strong movement toward action, and he needs to get ahead of it politically."

Legislature's plan

Scott isn't he only one who has been moved to action after the South Florida high school massacre.

“It has been one week since I visited Stoneman Douglas High School, but the scene of horror that we viewed was so troubling, it feels like we were there earlier today. I cannot imagine how those who survived the attack must feel as they face the vivid memories of that day,” Senate President Joe Negron, R-Stuart, said.

Negron joined other House and Senate leaders Friday in outlining proposals that could lead to some armed teachers in public schools and requiring that gun purchasers be at least 21 years old.

"The House and Senate have a very similar approach to what Gov. Scott proposed," Sen. Rob Bradley, R-Fleming Island, told News4Jax by phone.

House Speaker Richard Corcoran, R-Land O’ Lakes, said at a news conference that lawmakers are expected to spend $400 million to $500 million on the issues, though details were still being worked out.

Lawmakers want to allow teachers who go through extensive training and work under the direction of law-enforcement agencies to be able to carry concealed weapons at schools.

Also, they would increase the age to purchase long guns, such as rifles and shotguns, to 21, which is already the age requirement for purchasing handguns.

Lawmakers will not seek to ban semiautomatic rifles, commonly known as “assault” rifles, such as the one used in the Broward County murders.

“Nothing we will do in the State Legislature will fill the void created in the families of the victims, their school, or their community, but we can honor their memory by taking the appropriate steps at the federal, state and local levels to help reduce the chance that a tragedy like this could ever happen again," Negron said.

House Rules and Policy Chairman Jose Oliva and his colleagues already rejected a plan similar to Scott's proposed violent threat restraining order.

“We took a long, hard look at this,” said Oliva, a Miami Lakes Republican slated to take over as House speaker this fall. “Whenever you are going to deprive someone of something, you have to do it under a condition that provides clear evidence that that is necessary. In the way that we’ve seen it, giving people outside of either the authority or the understanding of what is clear and present danger -- a family member, a neighbor, or someone like that -- to directly make that appeal, we think goes beyond.”

Lawmakers are racing against the clock to pass a wide-ranging measure before the legislative session ends on March 9.

“Our job is to lead. Government has failed on multiple levels. It can never happen again. Our hope is that we will put together, jointly with the Senate, a proposal that will ensure it never happens again and we don’t fail our school students again,” Corcoran, R-Land O’ Lakes, told reporters.

Bradley, who serves as the Senate Appropriations chair, said he's confident that the lawmakers will finish the session as scheduled.

"I remain optimistic we will finish on time. It is a lot. The House and the Senate have already passed a budget. We just have to reconcile the two spending plans," he said.

For the breakdown of the Legislature's proposals, click here.