To prepare students for college and careers, the Common Core Mathematical Practice Standards propose teachers engage students in classroom discourse where they make sense of mathematics by working collaboratively and communicating their thinking. The purpose of this mixed methods study was to explore the relationship between a blended learning environment and the discourse students produce while in an AP Calculus AP course. Participants in this study are members of a large high school enrolled in either hybrid or virtual learning environments. Data were collected through recorded observations, coded using the Mathematics Classroom Observation Practices Protocol (MCOP[superscript 2]) and analyzed using statistical tests and thematic coding. The data in this study indicate there is an association between different aspects of discourse and the learning environment. Numerous themes arose from the 110 groups as they completed five different tasks. As there is a lack of research on the impact of COVID-19 on students' productive mathematical discourse while in a blended learning environment, the findings of this study will contribute to teachers' and educational stakeholders' understanding of how groups can create discourse regardless of their learning modality. [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.]