Describes a multiple-choice instrument that reliably and validly diagnoses secondary students' understanding of photosynthesis and respiration in plants. Highlights the consistency of students' misconceptions across secondary levels and indicates a high percentage of students have misconceptions regarding plant physiology. (CW)

Many researchers believe that prior knowledge is the single most important variable influencing learning. Learning in the classroom is determined or affected positively or negatively, to some degree, by the knowledge people bring to the classroom. This study was designed to: (1) assess fifth- and eighth-grade Korean students' misconceptions of…