President Donald Trump put forward a proposal to arm up to a fifth of teachers after hearing emotional appeals for action from students and parents still grieving from the Florida school massacre.

Trump floated the conceal-carry proposal after a White House listening session, where some students called for regulation of assault weapons, an angry parent called for hardened school security, and others just demanded 'change.'

After listening from a circle of participants, Trump floated his own idea, calling for arming teachers and coaches, and even bringing in Marines.

'Lets say you had 20 percent of your teaching force, because that’s pretty much the number' Trump said, describing how it might work.

President Trump suggested arming teachers during a listening session Wednesday at the White House with school shooting survivors and other gun violence victims who lost children in one of the nation's mass school shootings

President Trump (left) shakes the hand of Marjory Stoneman Douglas High School shooting survivors Carson Abt (center) and Ariana Klein (right) during a White House listening session on Wednesday

There are an estimated 3.2 million teachers or full-time equivalent teachers – which would put the armed force at 640,000 – larger than the U.S. Army, which is set to drop to 450,000 at the end of the year.

Trump said the teachers with guns would be 'adept at firearms' and would get 'great training.'

Trump also mentioned Marines, saying those armed on a sprawling campus like the one in Parkland, Florida would be 'spread evenly,' rather than having a single security guard.

He acknowledged it was a controversial idea. 'We can understand both sides. Certainly it's controversial,' he said.

Trump complained that the shooter 'should have been nabbed.'

But with teachers and coaches armed, 'That would've been the end of it.'

Trump said when there's an intruder, 'You will no longer have a gun free zone.'

At one point during the discussion he asked the audience's opinion of his suggestion to arm teachers.

The president's viewpoint was in the minority, according to the White House pool report.

Donald Trump met with survivors from the Parkland school shooting at the White House Wednesday

Marjory Stoneman Douglas High School student Samuel Zeif wipes tears next to Nicole Hockley of Sandy Hook Promise as President Trump hosts a listening session with high school shooting survivors and students to discuss school safety

The president's proposal seemed to be an about-face from where he stood during the 2016 campaign, if Trump's Twitter account had been any indicator.

Trump had tweeted that May: 'Crooked Hillary said that I want guns brought into the school classroom. Wrong!'

That was in response to Trump receiving an endorsement from the NRA and Clinton hitting him for it.

'This is someone running to be president of the United States of America, a country facing a gun violence epidemic and he's talking about more guns in our schools,' Clinton said on May 21, 2016.

Trump's tweet came later that night.

Though when appearing on Fox News the next day, the GOP nominee tried to have it both ways.

'I don't want to have guns in classrooms,' he said, objecting to the tweet. 'Although, in some cases, teachers should have guns in classrooms, frankly. Because teachers are, you know. Things that are going on in our schools are unbelievable.'

'You look at some of our schools, unbelievable what’s going on,' he repeated.

'But I’m not advocating guns in classrooms. But remember, in some cases, and a lot of people have made this case, teachers should be able to have guns. Trained teachers should be able to have guns in classrooms,' candidate Trump said.