This dissertation and all of my graduate work would not be possible without the support, guidance, and love of so many people in my life. Through each year at Illinois State University, I have been fortunate enough to encounter supportive, creative, and challenging souls that have shaped my journey thus far. I would first like to thank Dr. Cynthia Langrall. She and Dr. Edward Mooney encouraged me to continue toward the doctorate after finishing my master's degree. Their faith and support started me on this journey. Since then, Cindy has been ever present in my life giving me just the right amount of support and guidance throughout the process. I am so thankful to have worked with Cindy. Secondly, I would like to thank Dr. Beth Hatt. Beth has continually encouraged me to go out of my comfort zone and explore the many facets of qualitative research. Without Beth, I would not have had the courage to conduct this study. Each step of the dissertation process, she has been an amazing mentor and friend. I would also like to thank Dr. Jeffrey Barrett, Dr. Jae Baek, Dr. Craig Cullen, and Dr. Jennifer Tobias for allowing me to be a part of their work with teachers. Each of these professors provided me with support, guidance, and feedback as I learned how to study teachers at work. My work with them helped to spark my dissertation idea and shape my future research plans. I would also like to thank Dr. Tami Martin for her support throughout graduate school and for acting as one of my committee members. I am also grateful for the support and guidance of all of my other professors at Illinois 6. Example of event within matrix 7. Codes for event types 8. Mrs. Grey's interview tasks 9. Events that Mrs. Grey noticed during Interview 1 10. Events that Mrs. Grey noticed during Interview 2 11. Events that Mrs. Grey noticed during Interview 3 12. Events that Mrs. Grey noticed during Smartboard Lesson 13. Events that Mrs. Grey noticed during Relating Units of Measure Lesson 14. Events that Mrs. Grey noticed during Area Conservation Lesson 15. Summary of all student actions Mrs. Grey noticed 16. Mrs. Grey professional development questions 17. Events that Mrs. Purl noticed during Interview 1 18. Events that Mrs. Purl noticed during Interview 2 19. Events that Mrs. Purl noticed during Interview 3 x 20. Events that Mrs. Purl noticed during Smartboard Lesson 21. Events that Mrs. Purl noticed during Relating Units of Measure Lesson 22. Events that Mrs. Purl noticed during Area Conservation Lesson 23. Summary of all student actions Mrs. Purl noticed 24. Mrs. Purl professional development questions 25. Mrs. Brownstein interview tasks 26. Events that Mrs. Brownstein noticed during Interview 1 27. Events that Mrs. Brownstein noticed during Interview 2 28. Events that Mrs. Brownstein noticed during Interview 3 29. Events that Mrs. Brownstein noticed during Candy Filling Task 30. Events that Mrs. Brownstein noticed during Building and Filling Lesson 31. Events that Mrs. Brownstein noticed during Volume Assessment 32. Summary of all student actio...