A former Minneapolis elementary school teacher pleaded guilty Monday to several charges involving child sexual abuse material.

In May, Minneapolis Park police were called to Brackett Field to report that 35-year-old Preston Palmer was about to give a "substantial quantity of child sexual abuse materials to another individual."

Charging documents describe a group of people who work to uncover people soliciting minors for sexual acts. A 17-year-old member of the group told Palmer they were a 13-year-old boy, and charging documents say the two had conversations that were "overtly sexual in nature."

Palmer told the 17-year-old posing as the boy that he had 87 gigabytes of child sexual abuse materials with more than 1,000 videos on what he called his "pedophone." Another group member, posing as the boy's father, also spoke to Palmer. The two agreed to meet at a Minneapolis park.

When Palmer arrived at the park, the group members called police. Palmer was carrying a phone that had 18,466 files, and a preliminary review of 40 random files were "found to contain images of juveniles performing sexual acts," the complaint said.

Palmer faced 14 felony counts and pleaded guilty to six of them: one count of soliciting a child or someone believed to be a child through electronic communication to engage in sexual conduct and five counts of possessing pornographic work of a minor.

If his plea deal is accepted at his Dec. 3 sentencing, he'll receive a sentence of 10 years.

If you know of a child who may have been a victim of exploitation, call the National Center for Missing or Exploited Children at 1-800-843-5678 or visit the website.