On the internal structure of goals and beliefs

The theory ‚Teaching-In-Context' (abbreviated here as KGB), first introduced by Schoenfeld in 1998, has the objective of making the actions of a teacher in mathematics lessons rationally understandable. According to this theory, it suffices to locate the behavior as a function of the following three parameters: goals, beliefs and available teacher 's knowledge. Schoenfelds hypothesis implies that spontaneous alterations in the teaching trajectories can be explained through shifts in the structure of goals and beliefs. In the following we discuss a particular videoed classroom lesson with a remarkable turning point on the background of this approach.