The Volkshochschule is a state-aided adult education centre open for everybody that offers various relatively low-priced courses and trainings. In Saarbrücken, the VHS is located on Schlossplatz, next to the castle. They publish a new programme every year. The semester usually starts in September. Check out the different courses and download the programme from their website.
Subjects are, for example: all sorts of languages, historical and political subjects, culture, art, health, etc.