Understanding the IDEA System's Extraneous Variables. IDEA Research Report.

Research has confirmed the common belief that instructional outcomes are influenced by "extraneous variables." It is important to separate the contributions of the teacher from the contributions of extraneous factors to student learning, and that is the purpose of the IDEA system's adjusted ratings. To adjust scores on the IDEA Center's Diagnostic Form, five extraneous variables are assessed and taken into account. These include measures of: (1) course motivation; (2) work habits; (3) student effort; (4) disciplinary difficulty; and (5) size of class. This paper contains a brief definition of each of the extraneous variables, the relationships among the variables, and their impact on course outcomes. Some findings from previous research about the extraneous variables are presented. (SLD)