Plainfield police say 27-year-old Ashley Blumenshine was taken into custody after she was found in a car with a 16-year-old boy. She is charged with aggravated criminal sexual abuse.
Blumenshine teaches physical education at Plainfield North High School.
On Tuesday evening, two cars parked behind a Plainfield department store caught the attention of a police officer.
"He decided to check out the car, and when he got up there, there was a female in the driver seat and a young male in the back seat partially disrobed," said said Chief Bill Doster, Plainfield Police Department.
Police say a male Plainfield North student was in the car with Blumenshine.
"Obviously, she is innocent until proven guilty. But why somebody would even put themselves in a position like that to jeopardize their future," said Doster.
Blumenshine has been a teacher at Plainfield North since 2006.
The school district's spokesman says a substitute teacher has taken over Blumenshine's duties and counseling is being offered to students.
"For our students we convene special counseling services for the kids who requested and need such assistance and, of course, we will continue to work closely with the police and the state's attorney," said Tom Hernandez, Plainfield Community Consolidated School District 202.
Students tell ABC7 news that the arrest was the topic of conversation at school. Senior Matthew Busse has worked with Blumenshine doing lights and audio for the school's dance shows.
"I knew her personally. She was my older sister's teacher for two or three years and I have worked with her personally doing the dance shows and stuff, and I can't believe stuff like this would happen," said Busse.
The district says they will take appropriate job action pending the outcome of the case.