Conducted during the 2008-09 school year and published in 2011, this study evaluated the impact of a weekly, 50 minute per session chess intervention on grade 6-8 special education students’ end-of-course grades and performance on the Texas Assessment of Knowledge and Skills (TAKS). The sample was comprised of 15 treatment group students and 16 control group students. Treatment group students and control group students attended different schools that shared similar demographic characteristics. The schools were located within close proximity of one another. Researchers analyzed data using ANCOVA and found an effect size of 1.48 standard deviation units in math. The findings were statistically significant. This study was eligible for inclusion in the systematic literature review and categorized as a Tier III study. Although the schools share similar demographic characteristics and are located near one another, the article does not present pre-test scores, making it unknown whether the treatment and control students were similarly prepared prior to the intervention’s implementation.