Parent involvement in education has long been viewed as a pathway to increased student achievement. Although much research exists with regard to this topic, little examines this relationship specifically for students with disabilities in grades 1-5 despite being required by both the No Child Left Behind Act (NCLB) and the Individuals with Disabilities Education Act (IDEA). Representing nearly 13% of the school-age population demands a more in-depth examination of the potential for parent involvement to impact the achievement of an already disadvantaged subgroup. This study uses the Early Childhood Longitudinal Study 1998-99 (ECLS) publicly available data set to investigate the relationships between 3 forms of parent involvement (i.e. home, school, and community) and reading and mathematics achievement of students with disabilities. The ECLS 1998-99 Study followed approximately 21,000 students selected to represent nearly 220,000 students from kindergarten through eighth grade. For this study, 1,544 students with disabilities in grades 1-5 were selected for analysis. Only students with complete survey data were included. The effects of parent involvement upon reading and mathematics were measured while controlling for race, socioeconomic status, gender, age, family context, special education status at kindergarten, and first-grade reading and mathematics achievement as measured by the study. Analyses completed included both multiple regression and linear mixed effects models which revealed that, over time, all three involvement types affect reading and mathematics achievement. Both community and school-based involvement had positive effects while at-home involvement was found to negatively impact achievement. [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.]