Purpose. The purpose of this replication study was to describe the extent to which seven collaborative behaviors were demonstrated by general education teachers assigned students with disabilities, education specialists, and their administrators in selected California high schools that exceeded the state average pass rate for 10th-grade students with disabilities on the math portion of the California High School Exit Exam during the 2010-2011 and 2011-2012 testing cycle. Methodology. Six administrators, 10 math educational specialists, and 49 general education math teachers from the Bay Area in California comprised the sample for this descriptive ex post facto baseline study. Online questionnaires and telephone interviews were used to gather data. Questionnaire data were analyzed using descriptive statistics. Interviews were analyzed using qualitative methods. Findings. Administrators, general education math teachers, and math educational specialists (a) demonstrated collaborative behaviors of trust, focus on student learning, open and reflective dialogue, common vision and goals, and recognition to a moderate extent during school development as a learning community; (b) demonstrated risk taking and critical review of practices to some extent during their development as a learning community; (c) developed collaborative behaviors in stages over time; (d) identified 14 barriers that impede (i) development of a vision and mission that is developed with all parties involved; (ii) recognition of accomplishments; (iii) development and use of assessment instruments; (iv) sense of value and respect; (v) use of a wide variety of instructional ideas; (vi) understanding of phenomena through the use of facts and data; (vii) sharing of ideas; (viii) willingness to discuss violations of norms, school vision, and mission; (ix) constructive feedback; (x) review of achievement levels of students with disabilities; (xi) review of goal effectiveness on IEPs; (xii) review of instructional practices for students with disabilities; (xiii) review of instructional materials for students with disabilities; (xiv) discussing of academic progress for students with disabilities. Conclusions. The findings confirm that seven collaborative behaviors studied were (a) linked to improved student achievement; (b) dependent on trust; (c) developed over time; (d) collaborative behaviors were symbiotic; (e) must be inclusive of all in the learning environment. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]