Curriculum-based measurement (CBM) has evolved as a reliable and valid method for measuring and monitoring student performance in basic academic skills. While the efficacy of CBM for assessing reading skills is not in question, issues remain regarding whether or not a difference exists between CBM probes derived directly from the instructional curriculum and generic probes. The current study extends previous research comparing the utility of two types of CBM reading probe materials. Both types of probes were administered to 13 second grade students twice weekly for 5 weeks. No significant differences were found between the two probe types' measurement of performance or progress over time, which suggests that school psychologists and educational professionals can use generic or curriculum dependent probes in curriculum based measurement.