Each and every student, including students with disabilities, needs to be engaged in high-quality science instruction that moves beyond just memorization and recall of facts and toward critical thinking that supports informed decision making about current issues. There are notable achievement gaps between the science proficiency of students with and without disabilities, and these gaps widen as students progress to higher grade levels. The gaps in achievement may be symptomatic of gaps in opportunities for sensemaking within the general education science classroom. Using an explanatory sequential mixed methods design, the current study explored the relationship between teacher beliefs and opportunities to participate in sensemaking discussions in middle school science classrooms. Integrated findings from the study suggest that teachers' beliefs influenced the opportunities students with disabilities had to participate in sensemaking discussions and, at times, there was a mismatch between teacher beliefs and practice. This study addresses an important gap in the research literature on opportunities students with disabilities have for sensemaking in science classrooms, a grossly under researched area of inquiry. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]