Report Summary Effectiveness: MyTeachingPartner-Secondary (MTP-S) was found to have potentially positive effects on general achievement for middle and high school students. Program Description: MTP-S is a professional development program that aims to increase student learning and development through improved teacher-student interactions. Through the program, middle and high school teachers access a video library featuring examples of high-quality interactions and receive individualized, web-based coaching approximately twice per month during the school year. MTP-S uses the secondary school version of the Classroom Assessment Scoring System(R)-Secondary (CLASS-S) to define and observe effective teaching practices. Research: The What Works Clearinghouse (WWC) identified one study of MTP-S that both falls within the scope of the Teacher Training, Evaluation, and Compensation topic area and meets WWC group design standards. This one study meets WWC group design standards with reservations. The study included 2,237 middle and high school students in 12 schools in Virginia. The WWC considers the extent of evidence for MTP-S on the academic achievement of middle and high school students to be small for one student outcome domaingeneral achievement. There were no studies that meet WWC design standards in the five other student outcome domains and six teacher outcome domains, so this intervention report does not report on the effectiveness of MTP-S for those domains.