The purposes of this study were to develop and validate a quantitative instrument (Teacher Dispositions Index (TDI)) that measures the dispositions of effective teachers as specified by the Interstate New Teacher Assessment and Support Consortium (1991). To provide evidence of the TDI’s reliability and validity, we distributed the TDI to 105 undergraduate students enrolled in an instructional systems course in a College of Education at a Midwestern metropolitan university. The TDI could be used to assess teacher candidate dispositions over the course of pre-service preparation and to help candidates determine if teaching is an appropriate professional fit
