Introducing an observational measure of standards-based mathematics teaching practices: Evidence of validity and score reliability

The purpose of this study is to introduce a measure of standards-based mathematics teaching practices, the Mathematics Scan (M-Scan), and to examine its validity and score reliability. First, we define standards-based mathematics teaching practices based on eight dimensions that have emerged in recent conceptualizations by researchers and in the context of existing observational measures. Second, we present three sources of validity evidence: content review by experts, analysis of response processes of coders, and convergent and discriminant patterns with existing observational measures. Third, we provide evidence of inter-coder (or inter-rater) reliability through analyses of variance components and calculation of reliability coefficients, using the framework of generalizability theory. Results show the M-Scan holds promise as a useful tool in mathematics education research, measuring indicators of standards-based teaching practices unique to the subject of mathematics.