PINELLAS PARK — A Pinellas high school teacher was arrested Thursday after investigators got a tip that he had a sexual relationship with a student.
Jonathan Dunn, a 28-year-old math teacher at Pinellas Park High School, is charged with three counts of unlawful sexual activity with a minor and transmitting harmful material to a minor.
Police said a school resource officer received a tip about Dunn, who lives in Gulfport, this week and launched an investigation.
They determined Dunn and a female student had a relationship for about three weeks in December 2011, police said. The pair had sex both on and off campus when the girl was 16, police said. She is now 18.
Police said Dunn also had sexual conversations online with the girl. They are looking into allegations that Dunn had an inappropriate relationship with a second student, but that girl may have been 18 at the time.
"We're still investigating that," Pinellas Park Sgt. Brian Unmisig said. "Any time you have something like this happen, you're certainly worried you may have more victims."
Dunn's relationship with the girl became physical on Dec. 7, 2011, according to an arrest affidavit.
On that day, after school, the teacher persuaded the student to engage in oral sex in his classroom, the report said.
The next week, police said, the pair had sexual contact in Dunn's car after school.
Four days before Christmas that year, authorities said, the girl went to Dunn's home and had sex with the teacher.
School district officials said Dunn resigned Thursday amid an internal investigation. They also said they removed him from classroom duty last Friday after getting a tip that he had sent inappropriate text messages to a student.
"While news of his arrest is upsetting, this situation does not represent the exemplary teaching staff at Pinellas Park High School and the Pinellas County School District," the district said in a statement.
Dunn was hired by the district in 2010 and made $37,395 a year.
There was no a record of any prior disciplinary action against him in his personnel file. In addition to math, he also taught in the school's Criminal Justice Academy.
Dunn received the highest rating in his most recent public performance evaluation. He was rated as exceeding expectations in all but three of 25 categories.
"He is energetic, enthusiastic, and student centered," Michelle Topping, an assistant principal at the school, wrote.
According to his personnel file, he coached boys basketball, sponsored activities night teams, chaperoned the senior trip and assisted with "numerous" after-hours activities.
Dunn worked previously at Wharton High School in Hillsborough County from August 2008 to November 2009.
In his application with Pinellas, he described teaching as his "life's passion." He said he had worked as a private tutor since he had been in high school.
"I have always known I wanted to teach kids," he wrote.
Dunn was in the Pinellas County Jail on Thursday in lieu of $70,000 bail.
Times staff writer Peter Jamison contributed to this report. Kameel Stanley can be reached at email@example.com or (727) 893-8643.