Teacher Lisa Olson, with J.P. Holyoak, campaign chairman, urges support of legalizing marijuana for recreational use.

PHOENIX — Supporters of recreational marijuana brought out teachers, parents and school board members on Wednesday to argue that legalizing the drug is good for education.

J.P. Holyoak, chairman of the committee pushing the initiative, said the proposed 15 percent tax on marijuana would raise about $40 million a year, even after paying the costs of setting up a regulatory agency. Half of that would be earmarked to pay for full-day kindergarten, a program the state had funded but cut during the recession, with the other half for general education needs.

To put the amount of money that would be raised into perspective: State funding for K-12 education is $4.7 billion. And when federal and local dollars are added, the amount spent is more than $10 billion.

Teacher Lisa Olson said the alternative is money going to drug dealers.

“Now the cartels haven’t been very generous in sharing their profits with us,” she said. And Olson brushed aside questions of whether voters should also legalize and tax everything from prostitution to heroin if it raises money for schools.

“That’s another conversation down the road, maybe, maybe,” she said.

State Sen. Martin Quezada, D-Phoenix, a member of the Prendergast Elementary School District governing board, said voters will get a chance to decide two critical issues.

“The criminalization and prohibition of marijuana, is this a policy that’s working in Arizona?” he said.

Quezada said his belief is that it is not. He said the initiative gives voters a chance to have some input — however small — into funding of education.

“We have done a horrible job of doing that here in Arizona,” Quezada said. “This is one way we can address that problem here.”

Maricopa County Attorney Bill Montgomery, one of the leaders of the opposition to the initiative, chided supporters for using the carrot of improving education as a reason to legalize the drug.

“It’s a very perverse idea to suggest that you want to increase the availability of a substance that objective science now is demonstrating ... that adolescents and young adults that are exposed to marijuana are suffering lifelong consequences,” he said. That includes reduction in IQ, the early onset of psychosis and short-term impacts of memory loss and inability to learn.

And Montgomery was not convinced that limiting the sale of marijuana to adults will mean teens won’t get it. He said the experience with alcohol and tobacco, also substances supposedly available only to adults, shows that restriction doesn’t work.

Holyoak, however, said that ignores what’s already happening.

“The fact of the matter is that marijuana is currently available to anybody,” he said.

“It’s being sold at every single high school in Arizona today,” Holyoak said. “The war on drugs has failed.”

The most recent report from the Arizona Criminal Justice Commission found that 24 percent of more than 48,000 teens questioned said they had used alcohol in the last 30 days. By contrast, the figure for marijuana use was 13 percent.

That same report said three out of every four teens who said they used marijuana had obtained it from friends. And one out of every seven got his or her drugs from someone who can possess it legally under a 2010 voter-approved medical-marijuana law, a category that also can overlap with friends.

That law allows those with certain medical conditions and a doctor’s recommendation to obtain up to 2½ ounces of marijuana every two weeks from state-regulated dispensaries.

The initiative proposal would follow the lead of places like Colorado and Washington where the drug is legal for any adult. Proponents have crafted a plan they say will regulate it like alcohol, available from about 150 state-regulated stores and taxed.

Backers claim to have about 60,000 signatures of the more than 150,000 they need by next July to put the issue on the 2016 ballot.