KETTERING , Ohio-Matthew Ryan Koehler, a former Kettering City Schools music teacher, has pleaded guilty to four counts of pandering obscenity involving a minor. Koehler, 37, from Centerville, changed his plea from not guilty to guilty for these fourth-degree felonies. Each count carries a potential prison sentence of six to 18 months. The charges stem from the discovery of child pornography on his phone.
