Evidence-based instructional strategies in mathematics provide critical support related to academic achievement for students with disabilities. Data from national achievement assessments suggest that students with disabilities' academic growth in mathematics stagnates at the secondary level. Given that the majority of previously researched mathematics interventions focus on foundational and elementary mathematics skills, research on evidence-based practice with higher-level skills, such as algebra, may promote growth. Furthermore, algebra proficiency relates to increased educational and career opportunities. Current research on a core skill within algebra - solving equations - focuses primarily on the initial acquisition of the skill. In the current experiment, I designed a multiple-baseline study involving three middle school participants with specific learning disabilities to evaluate the effect of a frequency-building intervention on their rates of solving one-step equations. Results demonstrate immediate and significant positive effects on students' correct notations and drastic decreases in students' incorrect notations. Students generalized knowledge to untaught problem presentations. In pre- and post-think-alouds, students moved from using trial-and-error methods to using systematic procedures to solve equations. I discuss how the characteristics of the intervention supported students' overall improvement and discuss potential implications for both practice and future research. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]