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DENVER -- A first-year Denver elementary school teacher was placed on leave from her classroom with just a month left in the school year, but Denver Public Schools won’t say why.

Parents and former co-workers of Gabrielle Campiformio say she should have been removed at the beginning of the school year, not the end.

During a monthlong investigation, the FOX31 Denver Problem Solvers learned Campiformio never had a Colorado teaching license and was suspected of being under the influence of drugs in the classroom by former co-workers and some parents.

Cellphone footage shot by Campiformio’s last teaching assistant, who requested his identity not be revealed, shows Campiformio nodding repeatedly, her eyes barely open as she struggles to stay awake in her classroom of first-, second- and third-graders at Gilpin Montessori Elementary School.

“Two students got accustomed to making coffee for her because they were so used to her falling asleep,” the teacher's assistant said.

The man who shot the footage in early April said he did so because it was everyday behavior that he wanted to show as proof Campiformio wasn’t fit to teach.

“From seeing her one on one, it's either drug-related or related to being hung over all the time because it's just not a normal tired to slur your words,” said the teaching assistant, who also took video of students outside enjoying extra recess because he said Campiformio didn’t want to teach, adding many of the students didn’t know their ABC's.

He quit less than two months on the job, frustrated because he said principal Kimberly Riggins didn’t take his concerns seriously.

“After showing the principal the video, she never really addressed the issue with me again," the man said.

“Her voice was slurred, the kids would be like ‘What was that?’ And she would have to repeat again,” said Nabil Franco, who was Campiformio’s teaching assistant from October to February.

She also quit after she said Riggins ignored her concerns.

“She was like, 'OK, Nabil, thanks for telling me. I'll talk to Campfiormio).' That was it," Franco said.

The Problem Solvers showed the cellphone footage to Franco, who confirmed it was the sleepy behavior she witnessed for months.

“She couldn’t control her eyes” said Franco, adding Campiformio didn’t seem coherent enough to teach most days.

“It could have absolutely been drug use,” said another teaching assistant of Campiformio’s who requested anonymity.

This assistant worked with Campiformio for the first month of the school year but quit in September when she said her complaints to Riggins went nowhere.

“I even tried to address the part where she had no teaching license," the assistant said.

The Colorado Department of Education confirms Campiformio never obtained her teaching license and a spokewoman said it appeared Denver Public Schools was violating state law by using Campiformio in the classroom.

Campiformio did not answer her door when knocked and her attorney said she would have no comment.

But the Problem Solvers obtained an email sent just hours after our door knock that was written by Riggins. In the email sent to two members of the district’s administration team, Riggins writes, “(FOX31) knew she was on medical leave and was on drugs.”

The Problem Solvers only knew what the teaching assistants were saying until Riggins seemed to confirm drug use. The district refused to give up an April 21 email that was requested that was sent by a member of the Denver Classroom Teachers Association.

The union expressed concerns about the behavior and symptoms Campiformio was displaying in the classroom.

In early May, DPS leaders told the union its investigation found nothing wrong but didn’t tell the union that Campiformio had been placed on leave May 2.

When asked if the district waited too long to remove Campiformio, DPS spokesman Will Jones said, "I can't speak to any specifics in regards to any of our teachers because it's a personnel matter.”

When asked if having three assistants quit on the same teacher in one school year was a red flag, he said, “Again I can’t speak to that.”

But Jones said teachers are not drug tested before they are hired and can only be tested if a supervisor or principal suspects drug use, not a co-worker like a teaching assistant.

“A video in itself is not evidence. We have to have someone see it, and they have to see it on the job," he said.

Jones also said teachers can be hired without a license if they are in the process of getting one.

“If we find out that you're not getting your license, that's when we pull you from the classroom," he said.

But Jones would not explain why the district waited until there was just one month left in the school year before it pulled Campiformio.

“For the principal not to do nothing and know, it makes me mad,” said Angel Duran, a third grade mother of one of Campiformio’s students.

After her daughter complained about her teacher being sleepy, Duran visited Campiformio and was appalled by the behavior she witnessed.

“Just the way she was acting and throwing her head back and closing her eyes and moving her head. I'm like no she's not OK," Duran said.

Duran was mortified by the cellphone footage that was showed to her.

“Are you serious? Every day, my daughter had to see that," Duran said.

“Denver Public Schools, whenever something is brought to our attention, we act as quickly as possible because the stakes are so high we are dealing with people's children,” Jones said.

But parents and the three teaching assistants said her removal happened months too late, at the expense of student learning.

“I honestly think the principal and the assistant principal dropped the ball. They let those children down,” said the first teaching assistant who quit on Campiformio.

“Honestly, this year I don't think my daughter has learned anything. This year I think she's actually fallen behind,” Duran said.

Denver Public Schools won’t say if it drug tested Campiformio, but it did say she has not been offered a contract to teach again next year.

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