Examined instructional materials, teacher planning, instruction, and student conceptions related to an activity unit on plants and photosynthesis. Reasons are offered about why the teacher was unsuccessful in helping students replace their misconceptions with scientific conceptions, although the teacher knew this misconception existed. (JN)

The transfer of matter and energy from one organism to another and between organisms and their physical setting is a fundamental concept in life science. Not surprisingly, this concept is common to the "Benchmarks for Science Literacy" (American Association for the Advancement of Science, [1993]), the "National Science Education Standards"…