Educators are being encouraged to implement new instructional designs in an era where new standards, which promote student-centered learning, are being utilized and all students are expected to be successful on standardized tests. Consequently, there is a need for further research on the effectiveness of student-centered instruction. For that reason, this quantitative study, which was drawn from the constructivist and social learning theories, was conducted. Data were collected from 45 sixth-grade students from two classrooms. At the onset of the study, participants completed a 50 question pretest taken from the Reading and English/Language Arts Georgia Coach book to determine their prior knowledge of the grammar concepts to be covered. Subsequently, during the six-week research period, students in the experimental group were educated using cooperative learning and lessons developed based on Gardner's theory of multiple intelligences, while the control group received instruction via lectures. At the conclusion of the study, all participants completed a similar 50 question posttest to determine the amount of growth, if any, each student made after treatment was given. Pre- and posttest scores were recorded, gain scores were computed, and a t test was conducted to determine if a difference existed between the groups based on gain scores. Findings revealed that although the experimental group demonstrated improvement at a slightly higher level, the gains were not statistically significant. Nevertheless, this research will be beneficial to teachers as they search for instructional designs that will produce student success in middle school classrooms. Ultimately, this success will contribute to social change as it will provide students with the tools and confidence they will need to be successful in high school and beyond. [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.]