Mathematics teacher education programs vary widely in the learning opportunities they offer to prospective teachers. Improving the quality of teacher education necessitates an understanding of which of these learning opportunities have the largest impact on teacher preparedness. To understand this, there must be a meaningful method for assessing teacher preparedness. In this dissertation, I conducted a study that examined teachers' retrospective feelings of preparedness after completing a teacher education program and how those feelings relate to their actual preparedness, as evidenced by artifacts of practice. I present my findings in three manuscripts. In the first manuscript, I examined 11 early career teachers' retrospective feelings of preparedness to engage in effective mathematics teaching practices, reflection, and collaboration and what aspects of their teacher education program most impacted these feelings. The results indicate that the most important aspect of the teacher education program was a cohesiveness of the goals and ideas that were emphasized throughout. Additionally, completing student teaching in paired placements did not prevent graduates from having the background knowledge and skills necessary to engage in effective teaching practices in their own classrooms; however, these placements did not ensure graduates felt prepared to engage in collaboration or reflection. In the second manuscript, I developed a rubric to assess the alignment of mathematical tasks and learning goals to determine the relationship between teachers' feelings of preparedness to select tasks that align with learning goals and their actual preparedness to do so. I provide a description of the development and implementation of the Task And Learning Goal Alignment Rubric (TALGAR) using a Delphi model process and propose other possible uses of this rubric for researchers and practitioners. In the third manuscript, I examine the relationship between teachers' feelings of preparedness to select rich mathematical tasks and select mathematical tasks that align with learning goals and their artifacts of classroom practice. The results indicate that novice teachers' feelings of preparedness might somewhat, though not fully, align with their actual preparedness to select tasks that align with learning goals. This relationship was not as clear with respect to preparedness to select rich mathematical tasks. [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.]