Abstract: | Abstract How beginning teachers organize themselves to teach new or unfamiliar topics is an important issue for research. This paper discusses information about rivers in pre-service teachers' lessons taught to fourth grade students. Lessons were videotaped and transcribed for analysis. The data consisted of all information about rivers found in the lessons. Lesson content was analyzed for accuracy, coherence, centrality, over-simplification, and undue emphasis. Seven kinds of problems with lesson content occurred because the beginning teachers lacked sufficient knowledge about rivers. Inaccurate information was either presented or allowed to stand unchallenged in the lessons. The lessons lacked coherence, because the beginning teachers tended to make passing references to concepts. About twice as many of the lesson concepts were peripheral to the study of rivers, the problem of centrality. The relationships between some river-related ideas were misunderstood or ignored. Both physical and human geography concepts were consistently over-simplified. The recreational use of rivers was consistently over-emphasized. |