(WXIA) – Two more metro Atlanta teachers have been accused of having sex with students. So far, only one of the teachers has been arrested. The second arrest could come later, as investigators continue to conduct interviews and analyze possible evidence.

The teacher arrested Monday is at least the 12th teacher in Georgia arrested this school year accused of having a sexual relationship with a student.

Four of the suspects were Gwinnett County teachers. Gwinnett is the state’s largest school district. The 12 teachers arrested are from both urban and rural school districts.

John Seryak, a retired educator who is now with the organization SESAMEnet.org -- Stop Educator Sexual Abuse Misconduct and Exploitation, says schools and police do not release official statistics, but his group's research, nationwide, compiled a list of 459 teachers arrested in the U.S. for sexual misconduct with students in calendar year 2014, and 496 more arrested last year.

Seryak believes one major reason for all the cases is the illegal use of smart phones and social media.

"Access is a key factor," he said. "With students with cell phones all the time, and teachers with cell phones, there's that ability to communicate.... [some teachers] will actually target students they know are vulnerable."

But Seryak pointed out that the "secret" communications are also the reason many cases are exposed -- parents discover the teachers' sexting on the children's smart phones and laptops.

“A parent's role is absolutely key. And for those parents who discovered that and took action, kudos to them,” he said. “We need more parents like that to be on top of what their children are doing. Teachers shouldn't be communicating with their students other than on the school district's website. Public schools, private schools, charter schools should be safe havens and places of learning for children. There should be absolutely zero numbers of cases of teacher sexual misconduct. Well, this is not the case. We have hundreds across the nation. That's an epidemic. Especially since our expectation is that this would never, never happen. Well, it's happening. And it's happening in every state, it's happening in multiple school districts."

Training in how to recognize and avoid situations that could lead to improper relationships -- and worse -- is important for teachers, Seryak said. "But the overwhelming population of teachers, vastly overwhelming, don't need this kind of training, because they have good, strong professional [and personal] boundaries."

In general, though, he says every educator will benefit from ongoing, “specific training that focuses on Code of Conduct and Code of Ethics....[and] training about personal and professional boundaries.... Training will also enlighten educators to the dynamics and grooming behaviors of predatory teachers.”

Seryak says one of the most effective ways to reduce and stop such crimes is a united approach among educators.

"The education 'system' itself can be doing more with a call to action for teachers and teacher union leaders to come forward and demand training, legislative change, transparency, and accountability. There are literally millions of teachers across this nation and each of us should be speaking out against educator sexual misconduct, district policies and behaviors that put students at risk, and calling for more training. The nation's teachers could be a literal 'army' of advocates for change."

The charges against the teachers are felonies, and the teachers face decades in prison if convicted of assaulting the students -- inflicting wounds that could hurt the students for a lifetime.