Differentiation as measured by the Classroom Practices Survey: a validity study updating the original instrument

The Classroom Practices Survey assesses educators’ use of differentiated instruction with students achieving at average and high levels. The purposes of this study were to investigate if the Classroom Practices Survey (1) yields reliable and valid data from the groups for which it was originally designed and (2) can be used to evaluate teachers’ differentiation practices for students who achieve at low levels. Participants included 648 elementary teachers who completed the Classroom Practices Survey for students achieving at high, average and low levels. Confirmatory factor analyses revealed that the original six-factor model was not supported by the current data. Model fit was improved with a four-factor model, but did not reach the recommended values for good model fit. Further research and possibly modifications are needed before this tool is used by researchers and schools. This study highlights the importance of periodically evaluating instruments and revising them if necessary.