The purpose of this study was to develop a problem-solving instrument that could easily be used by a classroom teacher. The research questions were (1) can the Problem-Solving Skills Assessments (PSSAs) differentiate between students with varying levels of selected problem-solving skills? (2) Can the PSSAs measure student growth due to problem-solving events and problem-solving units? and (3) Does varying types of the assessment activities provide similar or consistent results? This study used multivariate analysis of variance with repeated measures to detect significant changes over time and a to look for significant differences between cohorts and interaction effects. There were significant differences (p = 0.000) in assessment detected by the PSSA for overall problem-solving ability as well as the four problem-solving skills: problem definition, problem planning, plan execution, and problem evaluation. Additionally, there were significant interactions for assessment by cohort for three of the problem-solving skills: problem definition, plan execution, and problem evaluation. Findings also suggest that in many instances, the PSSA is able to detect significant differences over time, and significant differences between cohorts. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]