Successful completion of Algebra I is very important for all students in the United States, because it is a high-stakes, gatekeeper course that determines access to additional mathematics (and many science) courses. However, a substantial proportion of students with historically marginalized identities do not gain access to Algebra I until much later in their academic careers than their middle-class, White, English-speaking, fully able peers. This is not only an issue of tracking individual students, but is also indicative of a more profound, institutionalized set of practices. Using a purposive sample, this research highlights the ways typical teachers make tracking and student-placement decisions. Teachers in this research reported a heavy reliance on (1) their own omniscience; (2) collaboration with students and families; and (3) an intense commitment to ensure all students succeed. [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/en-US/products/dissertations/individuals.shtml.]