Abstract
This longitudinal study of middle school science teachers explored the relationship between effective science instruction, as defined by the National Science Education Standards (NRC in National science education standards. National Academy Press, Washington, DC, Citation1996), and student achievement in science. Eleven teachers participated in a three year study of teacher effectiveness, determined by the LSC Classroom Observation Protocol (Horizon Research, Inc. in Local Systemic Change Classroom Observation Protocol. May 1, Citation2002) and student achievement, which was assessed using the Discovery Inquiry Test in Science. Findings in this study revealed the positive impact that effective science teachers have on student learning, eliminating achievement gaps between White and Non-White students. Case studies of three teachers, both effective and ineffective explore the beliefs and experiences that influence teachers to change, or not to change practice. This study provides justification for teaching science effectively to narrow achievement gaps in science and provides insight to stakeholders in science education as to how to support teachers in becoming more effective, through addressing existing teacher beliefs and providing experiences that challenge those beliefs.