The purpose of this quantitative causal-comparative study was to determine if there were statistically significant differences between 3rd-, 4th-, and 5th-grade reading teachers in the Northeast Unites States, defined as participants and nonparticipants in the LETRS® professional development, in terms of teachers' self-efficacy in student engagement, instructional strategies, and classroom management, as well as teachers' reading instructional practices. Bandura's self-efficacy theory and Charlotte Danielson's "Framework for Teaching" (FfT) provided the theoretical framework for this study. The study was conducted with a convenience sample comprised 174 teachers who completed the Teachers' "Sense of Efficacy Scale" and the "Framework for Teaching." Four research questions asked about differences between the compared groups in terms of four dependent variables. The results of nonparametric Mann-Whitney U tests found statistically nonsignificant differences between the compared groups in terms of student engagement subscale (U = 3270.5, p = 0.12), instructional strategies (U = 3520, p = 0.42), classroom management (U = 3581.5, p = 0.54), and teachers' instructional reading practice (U = 3539, p = 0.46). The results found no evidence of effectiveness of the LETRS® professional development in terms of the four dependent measures. [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.]