Most students come to biology with several naive but well-entrenched misconceptions about evolution. Among these are ideas about population growth, variation within populations, competition, heritability, and particularly natural selection. Over the last decade we have employed a number of different teaching strategies including cooperative learning, integration of lecture/laboratory, use of "readings" vs textbook, and investigative laboratories in an attempt to help students develop a more sophisticated understanding of evolutionary concepts. All but integration of lecture/laboratory have been applied in both large lecture classes with multiple laboratory sections and smaller classes with a single laboratory. Data will be presented from majors', non-majors', and mixed-majors' courses. Student-active investigations integrating lecture and laboratory activities were the single most effective factor in promoting richer understanding of evolutionary concepts, but Lamarkian ideas about natural selection remain nearly intractable.

Key words: evolution, laboratory, misconceptions, student-active