When some is not better than none: Effects of differential implementation of curriculum-based measurement

This study explored the effect of differential implementation of curriculum-based measurement (CBM) on math computation achievement of students with mild disabilities. In addition, selected variables associated with the quality with which teachers implement CBM were examined. Twenty-nine special education teachers each monitored two students with mild disabilities in math computation using CBM for 16 weeks. Results indicated that students whose teachers implemented CBM more accurately made significantly greater math gains than did students whose teachers (a) implemented CBM less accurately and (b) did not use CBM. Adequacy of planning time was associated with the quality of CBM implementation.