The purpose of this study was to investigate the effect of selected science experiences on fourth-grade students' concepts of Piagetian physical causality, namely, animism and dynamism. Vocabulary ability and Piagetian developmental stages were assessed by the "Concept Assessment Kit Conservation" and "Metropolitan Achievement Test." Three-hundred minutes were devoted to instruction during the treatment phase of the study, 150 minutes to teaching the cause of floating to the experimental group followed by 150 minutes to teaching the definition of the term "living." A control group was given 300 minutes of language arts instruction. Post-testing using the "Concept Assessment Kit Conservation" was done to identify subjects who had changed in developmental stage. Causal stage was assessed by means of two clinical interviews: the first variable dealing with students' concept of "living," and the second considering students' concept of the cause of floating. Findings indicated that experimental group performance was greater than control group performance. Differences between the sexes were also reported. Concludes that animism and dynamism can be taught to fourth-grade children and that children who were classified as concrete operational had acquired the necessary cognitive structures to conserve, do reversible thinking, and make multiple comparisons. (Author/SK)