In a rural Alabama school district, 38.46% of the students failed the reading portion of the high school graduation examination. While the teachers in the school district were trained to differentiate instruction according to ability and gender, the impact of gender-differentiated reading instruction was unknown. The purpose of this case study was to investigate high school students' perceptions of the effectiveness of gender-based reading instruction and teachers' perceptions regarding the most effective instructional strategies. Insights were provided by Sax's theories on the differences between female and male brain development, Vygotsky's theory of child development, and Tomlinson's theory of differentiated instruction. A qualitative case study design was utilized to investigate students' perceptions of the effectiveness of gender-based reading instruction and teachers' perceptions regarding the most effective instructional strategies. Data collected from 8 student interviews, 3 teacher interviews, and 6 classroom observations were coded to identify common themes and relationships. The positive aspects of gender-differentiated instruction in reading included improved concentration and academic performance. The negative aspect of gender-differentiated reading instruction was the challenge of interacting with the same gender. Teacher participant results revealed that instructional strategies were not gender sensitive, summarizing was the most frequently used strategy, and planning for males was a challenge. The study will contribute to positive social change by providing policy makers and school personnel with a clear picture of how to prepare reading lessons that include instructional strategies that meet all students' needs, thus helping to close the reading achievement gap among male and female students. [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.]