The predictive utility of cognitive abilities on reading, writing, and mathematics achievement domains helps inform high-stakes decision making, such as learning disabilities. An examination of differences in specific groups may increase understanding of obtained scores on cognitive ability and academic achievement standardized tests. One particular variable that may be especially valuable to consider is gender, due to empirically based differences in cognitive abilities and academic achievement. For example, there is oftentimes a female advantage in processing speed and writing, but a male advantage in visual processing. Yet, as these differences are well-established, consideration of how gender influences the prediction of cognitive abilities on academic achievement (i.e., gender bias) is additive in understanding not only gender differences, but the utility of commonly administered cognitive ability and academic achievement standardized tests. The Woodcock Johnson Tests of Cognitive Abilities, Fourth Edition (WJ IV COG) and the Woodcock Johnson Tests of Academic Achievement, Fourth Edition (WJ IV ACH) are a set of widely used tests in school psychology. The present study examined differential prediction gender bias of the WJ IV COG composite scores in predicting WJ IV ACH scores in reading, writing, and mathematics at different developmental grade levels (i.e., 1-4, 5-8, 9-12) with structural equation modeling techniques. Results showed evidence for slope and intercept bias, which are two forms of differential prediction bias, mostly with math and writing as the endogenous variables. Other trends and possible explanations are discussed. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]