Many students struggle to understand what they read. The purpose of my study was to determine the relationship between teachers' instruction of three processes believed to help readers to become more engaged (purpose setting, questioning, and predicting), students' use of these engaged reader processes, and students' comprehension development. My research occurred within a larger study investigating the efficacy of a complex intervention called the Interactive Strategies Approach--Extended (ISA-X; Gelzheiser, Scanlon, Hallgren-Flynn, Connors, in press), and addressed two research questions. For question one, I asked if the 1) fidelity of implementation and 2) percentage of time allocated to instruction of engaged reader processes predicted comprehension post-test scores, after controlling for comprehension pre-test scores and instructional group homogeneity. The research participants (drawn from the larger study) were intermediate-grade students who read with grade appropriate accuracy but limited comprehension and their teachers. Students were taught in small groups for roughly 50 sessions. Results indicated that the percentage of instructional time devoted to engaged reader processes and fidelity ratings were low and also not significant in predicting the post-test scores. However, certain correlations were significant. Fidelity had a higher correlation with the comprehension pretest scores as compared to the comprehension post-test scores, suggesting that teachers had instructional priorities other than the engaged reader processes for the students with the lowest entering scores. Moreover, the comprehension pre-test was significantly negatively correlated with the change score, indicating that students who began intervention with higher scores gained less. Since my quantitative measures did not correlate with the comprehension outcome, I then used a case study approach to see if I could identify other instructional variables that were related to student outcomes. For question two, I asked how two teachers, one whose students had typical change scores in comprehension and one whose students had high positive change scores, compared in their lesson plans and instruction. I examined a total of 12 students (six from each teacher) for the lesson plan comparison and eight students for the comparison of instruction. First, I coded their lesson plans utilizing eight variables that seemed to characterize the teachers' method of planning, to determine the similarities and differences between the two teachers in their planning of teaching the engaged reader processes. One factor that differentiated the high positive change score teacher from the typical change score teacher was the extent to which she planned to address all three of the engaged reader processes. Further, the lesson plans clearly indicated that the high-change teacher wrote more detailed plans, and planned on teaching the engaged reader processes in a way that better aligned with the guidance provided by the ISA-X Handbook (Gelzheiser, Scanlon, & Hallgren-Flynn, Connors, & Vellutino, 2013) and professional development. Then, I developed the Instructional Quality and Implementation Coding system (Allahverdi & Gelzheiser, 2017) to code the first few lessons given by the typical and high change score teacher about the use of purpose setting. I utilized my coding system to look for patterns between the typical and high positive change teacher with regard to their instruction of purpose setting that may have accounted for the discrepancy in their students' progress. I found that the high change score teacher had students who varied in their reading growth. This teacher's highest growth students, as compared to medium and low growth students, were more often provided with explicit introduction of how and why readers set purposes, feedback on purpose setting, and different types of scaffolding. They also set more purposes and returned more often to the purposes that had been set. In contrast, the typical change score teacher's students did not receive as much explicit introduction to the engaged reader processes and were provided with the most frequent inappropriate scaffolding related to purpose setting. These students did not set as many purposes and often failed to return to the purpose that had been set. My study supports previous findings that teachers vary in their ability to provide explicit instruction, model, and create a focused strategy-learning environment (Almasi & Fullerton, 2012). Case studies like mine have limited generalizability, so I recommend that future research be done in order to confirm or disconfirm the findings. Furthermore, since teachers can take up to two to three years to be able to teach strategies effectively (Almasi & Fullerton, 2012), I believe that longitudinal studies could be useful to examine the development of teachers in their instruction. (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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]