This paper describes a secondary analysis of the National Assessment of Educational Progress (NAEP) reading scores by gender. Data were national public 4th- and 8th-grade reading scores from composite and subscales for 2005, 2007, 2009, 2011, and 2013. Twelfth-grade scores for composite and literary experience from 2005, 2009, and 2013 and gain information from 2005 were included. Differences (p.<0.001; Cohen's "d" effect size) in reading average scale scores by gender were consistent across grade level and years with females scoring higher than males. Results are congruent with a previous study of NAEP reading by gender across fourth-, eighth, and twelfth-grade-levels for 1994, 1998, 2000, 2002, and 2003 (Klecker, 2006). Discussion includes comparisons with cross-cultural international assessments and possible explanations for the widely-observed gender difference in large-scale standardized reading assessments.