Zachary Scheich, using the alias Zak Hess, has been charged with two counts of sexual assault and one count of sex trafficking a minor using an electronic device.
All of the victims identified are female, and police said Mr Scheich allegedly communicated with them via phone and computer.
Investigators said he allegedly attended multiple schools in the Lincoln Public Schools district during the time he was incognito. He graduated from the same school district in 2015, police said.
The school district learned that an adult man was impersonating a student during its 2022-2023 school year using the name Zak Hess. The district then alerted police on 1 June, which started an investigation into the alleged impersonation.
Police said Zak claimed to be 17 and he began the year attending Northwest High School and later transferred to Southeast High School for the second semester of the year, according to USA Today.
Officers eventually determined that the man claiming to be Zak graduated from Lincoln Public Schools in 2015, and found he was actually 26.
Records from the district show he was in attendance as Zak Hess for 54 days. Mr Scheich is 5-foot-4 and 120 pounds, allowing him to blend in with the students at the high school.
Once police determined the man posing as Zak had contact with juvenile students they were able to secure an arrest warrant.
The district responded by sending out an alert to families at both schools which provided a summation of what had occurred.
According to the district, the man began attending Northwest High School in October 2022 and then transferred to Southeast in January of 2023.
The district received a tip on 31 May that an adult man may have been attending the school disguised as a junior. After receiving the tip, the district contact the police and provided them with the information it had received.
Police say they confirmed this month that Mr Scheich enrolled and attended the high schools, leading to his arrest on Thursday.
The district distributed his photo to school officials and warned them not to allow him on the premises. It further explained that Mr Scheich allegedly faked documents to enrol himself in the school. The district said it would review its enrollment process to prevent future abuse.
“Some parents don’t vaccinate, some homeschooled kids don’t have transcripts when they come in, we have kids from across the world who come in who don’t have birth records,” Lincoln Public Schools Director of Security Joe Wright said during a press conference.
He said the district has a “statutory responsibility” to provide education to any child 20 years old and younger, according to the Lincoln Journal Star.
“What’s provided to us is sometimes not as thorough as we like or as proof positive as this kind of case would make you think, but that’s what’s required of us.”
Police are investigating potential victims relating to the impersonation.