Description: This article discusses a fixed effects panel data model. Abstract: Statistical models that combine cross section and time series data offer analysis and interpretation advantages over separate cross section or time series data analyses (Matyas & Severstre, 1996). Time series and cross section designs have not been commonplace in the research community until the last 25 years (Tieslau, 1999). In this study, a fixed effects panel data model is applied to the National Education Longitudinal Study of 1988 (NELS:88) data to determine if educational process variables, teacher emphasis, student self-concept, and socio-economic status can account for variance in student mathematical achievement. A model that includes seven independent variables accounted for 25% of the variance in student mathematical achievement test score. The study provides educational researchers with an applied model for panel data analysis.