This project was initiated (1) to determine the effects of three experimental "modern" programs in secondary mathematics--the Ball State, University of Illinois Committee on School Mathematics (UICSM), and the School Mathematics Study Group programs--on the attitudes and interests pupils develop toward mathematics and (2) to examine factors and conditions related to these effects. The project consisted of a number of separate studies which involved 126 pairs of secondary mathematics ninth grade classes in school districts from a five-state area--Minnesota, Wisconsin, Iowa, and North and South Dakota. The results of the investigation revealed (1) the experimental programs had little differential effect, in comparison to conventional programs, on the attitudes and interests pupils developed toward mathematics, (2) information obtained from the self-report indices indicated that pupils instructed with the Ball State program tended to develop less positive attitudes and interest toward mathematics than those instructed with conventional programs, and (3) there was evidence that the UICSM program, according to the behavioral indices, may have contributed to the development of more positive attitudes and interests than the conventional program. (RP)