The Students Understanding eNergy (SUN) Project reports significant long-term effects on biology teacher knowledge and self-efficacy regarding biological energy transfer. Teachers use a hydrogen fuel cell and manipulatives to develop a model of energy transfer based on electrons moving in thermodynamically spontaneous reactions.

We have begun a randomized, controlled trial of the effectiveness of a new way of teaching photosynthesis and cellular respiration. Key innovations include: 1) The use of a hydrogen fuel cell to illustrate four key principles: the relative tendencies of substances to give away electrons, the electron donor, the electron acceptor, and the fact that moving electrons can do work; 2) Comparing the hydrogen fuel cell and how living things are powered using those principles and rapid‐prototyped model components in the context of nested trays; 3) An animation that toggles between the hydrogen fuel cell and cellular respiration; and 4) A mechanical model of the ATP synthase. Teachers who attended a workshop increased their content understanding as reported at the NARST 2010 Conference. Here we focus on changes in classroom practice documented through videotaped focus groups, online reporting, and classroom observations of treatment and control groups. These data will inform future hierarchical linear modeling of content understanding effects in students. Implications for undergraduate education will be discussed. This work is supported by the US Dept of Education's Institute of Education Sciences.