A controversial new law allowing some Florida teachers to carry firearms in classrooms went into effect Tuesday.

The law, an expansion of the states Guardian Program , was passed in response to the 2018 shooting at a high school in Parkland, Florida, that left 17 people dead. The program initially allowed certain school employees or hired guards to carry weapons but was expanded by Republican Gov. Ron DeSantis in May to include teachers who meet certain training standards if their school district approves.

Guardians must pass psychological and drug screenings and undergo at least 144 hours of training, according to the Florida Department of Education. Those who enroll in the program receive a one-time stipend of $500.

The Coach Aaron Feis Guardian Program was named after a Marjory Stoneman Douglas High School coach and security guard who died while shielding students.

Guardians are armed personnel who aid in the prevention or abatement of active assailant incidents on school premises, a description of the program says. They are either school employees who volunteer to serve in addition to official job duties or personnel hired for the specific purpose of serving as a school guardian.

Across the state, 39 counties participate in the Guardian program, although some school districts have declined to take part. The superintendent of the Miami-Dade County district told the Miami Herald earlier this year that, although it planned to increase the number of armed officers in schools, it would not arm teachers .

That opinion was also echoed in Broward County, which includes Marjory Stoneman Douglas High.

We do not believe arming teachers is the best way to make our schools safe, Superintendent Robert Runcie told the Herald at the time.

Cameron Kasky, a gun control activist and a survivor of the Parkland shooting, excoriated the measure in an interview on Tuesday, telling CNN s Anderson Cooper it seemed like one of the most dangerous things that we could be doing.

Schools are enough like prisons already, heaven knows we dont need to scare these children with knowing their teachers are armed, Kasky said on CNN. The thought that their teachers, a force of authority, are going to be armed? That is detrimental to our generation.

Its unclear how many teachers have elected to be trained as part of the program because the state doesnt track that information. The Herald reported that 1,084 Guardians had been assigned to schools across Florida as of September.