Science education reform may fall short of its potential to reduce educational disparities if the challenges are interpreted using strictly reductionist approaches. Taking a cue from school effectiveness research and reframing our approach using systems thinking, this study examined school-level variables associated with equitable science achievement. In particular, this study explores the concept of trust in relation to science education. Building upon a substantial body of research literature, we offer refined conceptualizations of schoolwide trust along with the findings that trust fluctuates according to the type of interpersonal relationship, that teacher views of the school principal's trustworthiness are considerably more variable than views of fellow teachers' trustworthiness, and that school wide science achievement is associated with perceptions of the school principal's trustworthiness. This study supports the view that trustworthy professional relationships are one of several complementary organizational resources that promote effective and equitable science education. Moreover, our study identified aspects of school trust corresponding to school-level student science outcomes, and these differed from results reported elsewhere for math and reading/language-arts achievement.