Sex Differences in Educational Achievement: A Longitudinal Study

Research on sex differences in achievement has generally been concerned only with mean differences. In addition, such studies have frequently been limited to single grades or cross-sectional comparisons of several grades. To investigate the relationship between gender and achievement, and the change in this relationship over time, a sample of 4875 females and 4497 males tested with the Iowa Tests of Basic Skills each year from Grade 3 to Grade 8 was obtained. The interaction between sex differences and achievement level was also investigated. For this sample females had higher levels of achievement on the Spelling, Capitalization, Punctuation, Language Usage, Reference Materials, Mathematics Computation, and Reading Comprehension tests. The differences were largest for below average students. On the language tests the differences occurred at all points of the distribution and were substantial. Males showed superior achievement on the Visual Materials (maps, graphs, and tables), Mathematics Concepts, and to a lesser extent Mathematics Problem Solving tests. On these tests the largest differences occurred above the median. On Mathematics Concepts and Problem Solving tests the differences were at or above the 70th percentile and tended to arise in later grades. Males scores were more variable in all areas but vocabulary, and the differences in variability increased across grades.