A family therapist delves deeper into the psychology of children and lying.

ATLANTA — Case Closed -- That's what Atlanta Public Schools say about the case where a student claimed she was grabbed by a man with a gun on the playground at Deerwood Academy in southwest Atlanta.

11Alive's La'Tasha Givens spoke with a family therapist about the psychology of children and lying.

There are several recent cases making headlines where children have said they were harmed or threatened, and ultimately the claims ended up being not true. In one Atlanta case, the claim prompted a school lockdown.

Last month, a sixth-grader in Virginia said a group of boys held her down and cut her dreadlocks at school. In August, an 11-year-old girl in Paulding County told her parents a man in a white van tried to abduct her. This past Monday, a student at Deerwood Academy said a man with a gun grabbed her while she was on the school's playground.

In each of these cases, law enforcement agencies said the students lied about what happened.

On Friday, APS laid out evidence it said went against the Deerwood student's claims.

"In our screenshot, we see an unknown male who first appears on our screen at 12:20 -- He's coming from Hogan Road," said Atlanta Public Schools Chief of Police Ron Applin.

RELATED: Student's claim she was nearly abducted by armed man on playground 'unfounded,' APS says

The surveillance video showed portions of the playground. APS Police said the student was only out of frame a short time and cameras did not show her having contact with the man. But it did show the first time she told her teacher that something had happened.

"At this point, the student reported to the teacher that a man grabbed her," Applin said.

But police said the child's story changed as they talked to her more about the incident.

"We need to wrap our arms around that child or the children in these cases where they have told a story and kept up with a certain story," said family therapist Dr. Shatavia Thomas.

11Alive spoke with Dr. Thomas about the psychological aspect of children lying.

"Lying is developmental as opposed to pathological," Thomas said.

RELATED: Girl on playground nearly abducted by armed man, police say

She said that younger children have vivid imaginations and have a harder time separating fact from fiction.

According to the website BrandonGaille.com, 90 percent of children learn the concept of lying by age 4.

By the teenage years, according to the Journal of Youth and Adolescence, 82 percent of teens lie to their parents about money, alcohol, drugs and sexual encounters.

Dr. Thomas said that in many cases, there is a reason for the lie. She said that parents should try to find out how the false story is serving the child.

"A cry for help defiantly might come into play if your child -- let's say -- may have been supervised by someone else and you're not sure if there are any kind of indications of avoidance of a certain place or certain person or experiences," she said.

Dr. Thomas also said that parents should ask if your child has had a traumatic experience because it is possible that they may not have told you about it.

As for the APS story, the school district said that they plan to place a fence around the school.

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