Prophecy Effects and Tutorial Instruction for the Disadvantaged Child1

In what has become one of the most widely-publicized educational experiments of the decade, Rosenthal and Jacobson (1968) found support for the premise that one person's prophecy of another's intellectual performance can come to determine that other's intellectual performance. Their results indicated that a randomly chosen group of children, of whom teachers were led to expect marked intellectual growth, achieved significantly greater IQ gains than did control subjects. But reviews by Thorndike (1968) and Snow (1969) have raised serious questions about the legitimacy of the inferences drawn from that study. These critiques focus on two main points. First, analyses in the now famous experiment were performed on IQs derived from raw scores obtained with the TOGA (Tests of General Ability) which was chosen partly because it would probably be unfamiliar to teachers. Thorndike (1968) and Snow (1969) point up the inadequacy of the TOGA IQ norms for the youngest children tested-those for whom the reported prophecy effect was shown most clearly. Second, the reviewers call attention to the fact that the difference in mean gain between experimental and control groups was essentially zero for all grades except the first two. A methodological issue which has not yet been elaborated, however, is that all testing in the Rosenthal and Jacobson experiment This research was supported by a grant to the first author from the Center for Research and Advanced Studies at San Jose State College. The authors thank Mr. James Henman for his assistance in collecting the data for the study. 2 Requests for reprints should be sent to Robert J. Pellegrini, Department of Psychology, San Jose State College, San Jose, California 95114.