The purpose of this study was to assess the effects of the Curriculum Based Measurement of Spelling (CBM-S) and direct spelling instruction on students’ achievement in spelling. A total sample of 95 third-grade students participated in the study. This article presents a comparison study of three classrooms: CBM-S and direct spelling instruction, CBM-S with no direct spelling instruction, and a control group that used the traditional way of spelling assessment. The intervention was implemented for 18 weeks. The results indicated that students achieved the greatest gains in spelling when both direct spelling instruction and the CBM-S were applied.
