The purpose of the study was to determine if there is a difference in mathematics mean scale score growth on the MCT2 mathematics assessment between students taught by national board certified teachers (NBCTs) and those taught by non-NBCTs in a low socioeconomic, high minority, Title I school. For this study, a causal-comparative research design and a statistical analysis procedure of ANCOVA were used to answer two research questions: First, is there a statistically significant difference in mathematics mean scale score growth on the MCT2 mathematics assessment between fourth grade African American and Caucasian students taught by NBCTs and those taught by non-NBCTs, while controlling socioeconomic status and 3rd grade MCT2 mathematics scale scores? Second, is there a statistically significant difference in mathematics mean scale score growth on the MCT2 mathematics assessment between fourth grade students by socioeconomic status based on eligibility for free/reduced or full pay lunch taught by NBCTs and those taught by non-NBCTs, while controlling race and 3rd grade MCT2 mathematics scale scores? The results of the analysis for research question one indicated that there was not a statistically significant difference in mathematics mean score growth on the MCT2 mathematics assessment between students by race taught by NBCTs and those taught by non-NBCT. African American and Caucasian students taught by NBCTs had a comparable mathematics mean scale score growth with African American and Caucasian students taught by non-NBCTs. The results of the analysis for research question two indicated that there was a statistically significant difference in mathematics mean score growth on the MCT2 mathematics assessment between students by socioeconomic status based on eligibility for full pay lunch taught by NBCTs and those students taught by non-NBCTs. Students identified as full pay lunch taught by NBCTs had a higher mathematics mean scale score growth than those students identified as full pay lunch taught by non-NBCTs. Students identified as free/reduced lunch status taught by non-NBCTs had comparable mean scale score growth with those students identified as free/reduced lunch status taught by NBCTs, but not statistically significant. [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.]