How many movies have Horst Sieger and Kurt Matthäus collaborated on?

They have worked on 5 movies together! Their first movie together was Das Sexabitur (1978) while their highest rated movie together was Verbotene Spiele auf der Schulbank (1980). They have not worked together since Verbotene Spiele auf der Schulbank (1980). They are most known for their comedy films together.