This study describes the rationale of using microfossils in an instructional program to reveal earth history in public schools. Five foundation skills activities, plus 20 micropaleontologic inquiry activities and the Illustrated Catalogue of Common Foraminifera, are the Learning Resource Nucleus (LRN). The foundation skills activities provide self-instructional units designed to develop individual investigative proficiencies. Ten fundamental concepts unifying the 20 micropaleontologic inquiry activities provide an understanding and reasonable interpretation of earth history. Two activities demonstrate each of the 10 fundamental concepts. The format followed in each of the 20 micropaleontologic inquiry activities is: activity title (in the form of a question), untitled introduction, background information, activity operations, interpreting results, and references for further investigation. (Author/BR)