Previous research concerning the cognitive abilities of high school students has indicated that a substantial number of students enrolled in secondary science courses do not conceptualize at the formal-operational level. Further, results indicate that achievement levels in chemistry coursework are significantly affected by, not only cognitive…

Describes a study which was designed to determine the effect of a 25-hour introductory qualitative analysis course on high school students' understanding of formal concepts related to electrolytes. Suggests that introductory concrete experiences better prepare students to deal with more formal abstract concepts. (TW)