(TCIDOS) is a direct observation interval recording system that measures the occurrence of teachers’ instructional strategies and subsequent child behaviors. For the purpose of the BEST in CLASS efficacy study, the TCIDOS is administered in both coaching and comparison classrooms to determine the outcomes of BEST in CLASS on teacher strategy use and teacher-child interactions. In coaching classrooms, the TCIDOS is also used to provide graphical feedback during coaching. Observation sessions last a total of 15 minutes per teacher-child dyad. In the 15-minute observation session, there are a total of sixty, 15-second intervals. Each interval is broken down into a) 10 sec observation period and b) 5 sec recording period.