This qualitative study examined instructional assistants' (IAs) and teachers' perceptions of culturally responsive and quality instructional practices for young children, especially those from various cultural and linguistic backgrounds and those who might have disabilities from low socioeconomic families, in Head Start classrooms. In two focus groups, one for instructional assistants (n = 5) and one for teachers (n = 6), participants responded to open-ended interview questions regarding their experiences and understanding of young children, families, and personal incidents related to culturally responsive practices and providing quality instruction for all children and families, especially children with disabilities. Several themes emerged through a constructivist grounded theory, critical early childhood perspective, and analytic process: children and families, open to learning, experiences of marginalization, powerless, myth of merit, and fear. Organizational categories--culturally responsive, children with disabilities, and perceived ability to enact each--resulted in each group's unique definitions of each. Themes within the organizational categories varied for IAs and teachers. Suggestions for future research and practice within Head Start classrooms and other programs and policy implications in early childhood education 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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]