This study examined the features of the classroom discourse in eight Algebra I classes from two urban high schools with diverse student populations. In particular, by using the discursive analysis perspective, the type of communication between teachers and students was examined. The study investigated to what extent teachers' patterns of discourse change as a result of the number of ELLs present or their particular teaching experiences and ESOL endorsement. Furthermore, the impact of teachers' cultural and linguistic backgrounds upon ELLs' mathematics experiences was explored, particularly the teachers' patterns of discourse and adjustments to their "teacher talk," or modifications of instructions that contributed to ELLs' engagement in the mathematics classroom. Data analysis from various sources (observations, video-recordings, frequency counts, interviews, the teachers' self-evaluations, and the researcher's and the ELLs' evaluations) indicated that to some extent all teachers changed their patterns of discourse simply due to the presence of ELLs, regardless of the total number in the class. Teachers with more teaching experience and with ESOL training had a smaller number of ELLs in their classes, whereas in both schools the novice teachers were assigned to teach classes with the highest number of ELLs. The novice teachers frequently used almost the same strategies as their more experienced colleagues did. Yet the qualitative analysis of the "type of modifications to their speech they made," the "type of questions they asked," and the "provision of information of higher cognitive demand according to Bloom's Taxonomy" indicated that even though all teachers needed improvement in using these strategies, the more experienced teachers with ESOL training applied those strategies to a fuller extent. They more often "used slower and simpler speech" and "different questioning techniques" sensitive to the ELLs' level of English language acquisition (i.e., "pre-production," "early-production," and " speech emergence") and "provided the students with content specific, enriched information." However, they still did not ask enough questions that could provide the ELLs with opportunities to justify and explain their opinions, and rarely led the discussions to a point which could move the ELLs to the highest level of the subject-specific literacy--"intermediate speech" and fluency in mathematics in English. [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.]