The ability to think and solve problems quickly is a necessary skill for success in education (Flanagan, Ortiz, Alfonso, & Mascolo, 2006; Proctor, 2011; Taub, Floyd, Keith, & McGrew, 2008). This leaves students who struggle with speeded tasks at greater risk for not meeting the educational demands in the classroom. Modern intellectual taxonomies, as well as a more thorough understanding of cognitive mediation effects, have led to more reliable identification of these students (Floyd, McGrew, Barry, Rafael, & Rogers, 2009; Kail, 2000, Kail & Salthouse, 1994; McGrew, 2012). However, little-to-no research exists investigating the stability of processing speed (Gs) as it pertains to intervention and treatment for Gs ability deficits. The following study sought to identify children with low Gs ability while intervening daily using a school wide math fluency program with the intent of increasing global Gs over time. One hundred seventy-four second and third grade students were administered three Gs ability subtests from the WJ-III COG over time to assess Gs stability when compared to a control school. Results of the study indicated global Gs grew consistently across all Gs ability levels for both school groups. Limitations and implications of future research and practitioners are also discussed.