Purpose: This study explored a theoretical model proposing direct and mediated effects for principals' characteristics--principals' information-processing mechanisms (PIPMs) and instructional leadership (IL)--with organizational learning mechanisms (OLMs), for schools' OLMs with teachers' characteristics--teachers' affective commitment (TAC), collective teacher efficacy (CTE), and teachers' job satisfaction (TJS)--and finally, for teachers' characteristics with students' achievements on national math and science tests. Design: Data were collected from a multisource survey of a random sample of 130 elementary school principals representing Israel's full socioeconomic range, 1,700 teachers from those schools, as well as data on those schools retrieved from the Ministry of Education data set. Data were aggregated at the school level for structural equation modeling (SEM) analysis. Findings: Analysis from SEM confirmed that IL emerges as a prominent mediator between PIPMs and OLMs. OLMs emerged as a prominent mediator between IL and the three teachers' characteristics. TAC and CTE were significantly directly related to students' math and science achievements. Finally, OLMs promoted students' math and science achievements only through CTE. Implications: The relationships found for both principal characteristics (PIPMs and IL) with OLMs in schools highlight principals' potentially important role in promoting collective learning within schools through utilization of OLMs, which can predict critical teacher characteristics (TAC, CTE, TJS), which in turn can predict school effectiveness measures (i.e., students' achievements).