Zespół Szkół Ogólnokształcących im. A. Mickiewicza in Kluczbork is a general secondary school complex currently consisting of 3rd Year of middle school and general secondary school. The origins of the school date back to the 19th century. Its founder was Simon Cohn from Germany. The first patron of the school was Gustav Freytag – a German writer and a dramatist.  
In 1995 the school celebrated its 50th anniversary. On this occasion, it was given a new patron - Adam Mickiewicz – an outstanding Polish writer.

The building is located in Mickiewicza Street. There are around 70 teachers and about 700 students attend the school. They come from Kluczbork, nearby villages and towns and also from Ukraine and Belarus.