This study evaluates a model of social capital where support from parents, peers, teachers, and mentors (SOS) was hypothesized to mediate the link between students' abilities to mobilize support (MOS) and four school-related outcomes: academic, behavioral, emotional, and career outcome expectations. Survey data from 206 high school students with disabilities and 16 special education teachers in six school districts across three states were collected. Results from structural equation modeling, with bootstrap tests of indirect effects, indicated that SOS mediated the links between MOS and two of the four outcomes: emotional well-being and career outcome expectations. Invariance testing revealed significant differences for boys and girls. Implications for research and practice are discussed, including the need to distinguish between social capital and the process of capital formation, and the need to consider the role of students with disabilities in the process of social capital formation. [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.]