In response to the increasing linguistic and cultural diversity in US schools, in-service teachers are faced with the significant challenge of addressing both the linguistic and instructional needs of their multilingual learners (MLLs). This study provides evidence of the linguistic obstacles faced in the academic mathematics classroom and how "language is implicated in the teaching of mathematics." This qualitative study is informed by transformative learning theory. Data collection focused on written reflections through weekly discussions, posted in an online group forum, which allowed the teachers to read and comment on each other's understandings of the required article readings and related discussion questions. These online forums allowed the teachers to share new ideas, personal perspectives, ask follow-on questions, or in any other way "relate the [weekly] course content to [their] real-world teaching experiences" (syllabus). Weekly summaries were also required, submitted directly to the instructors and not made available to other participants. Each of these submissions addressed the general topic of the week, but could also include any perspectives on the course content, classroom observations, and reflections on discussions (syllabus). Participants' personal, increased ideological awareness and transformative learning experiences from these written sources reflect their unique classroom situations and beliefs across a number of relevant themes, though due to limited space, only two will be presented: the academic language of math, and first language use in the classroom. Data analysis demonstrates how participants came to recognize that math is not a "universal language" and instead that the academic linguistic complexity is highly contextualized and requires specific pedagogical strategies to support the simultaneous acquisition of language and academic content. In doing so, participants commented on the importance of having this realization and the positive impact it has on their understanding of their MLLs. Consequently, they realized that teaching practices would be improved by including a focus on language as well as content. Participants also gained awareness of the importance of respecting all students' prior knowledge, which in every classroom must be shown as a beneficial contribution to learning. In particular, the equitable pedagogical practice of encouraging and supporting their students' first language use in the classroom provided the teachers with opportunities to confront the prevalent ideology of English monolingualism; that is, in the US context, there is the common misconception that when learning English it should be in an English-only context and where any language other than English should be excluded to the point of banning other languages. By confronting this ideology and recognizing the significant diversity in their classrooms, teachers discovered that all students' languages must be considered as valuable resources and included in learning. Awareness was also raised about the reality of academic language requiring four to seven years to be acquired (Cummins, 1984). This was cited by the teachers as a critical piece of knowledge they needed. They also recognized that expectations must be kept high because, regardless of current English language proficiency, students are capable of thinking critically and engaging in high-order thinking with the appropriate scaffolds. When both the language complexity and support from the teachers mirror students' language proficiency levels (Gibbons, 2002, 2009), then the students' ability to engage in critical discussions will be greatly improved. As a result, participants developed a new commitment to support the long-term language learning of their students and provide opportunities for extensive language practice in the mathematics classroom. (Abstract shortened by ProQuest.). [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.]