Research on the interaction between student characteristics and instructional methods is important because it is commonly assumed that different students learn in different ways. That assumption is best studied by investigating the interaction between student characteristics and different instructional methods. The study of that interaction received its greatest impetus with the publication of Lee Cron-bach and Richard Snow's Aptitudes and Instructional Methods in 1977, which summarized research on the interaction between aptitudes and instructional treatments, subsequently abbreviated as ATI research. Cronbach and Snow indicated that the term aptitude, rather than referring exclusively to cognitive constructs, as had previously been the case, was intended to refer to any student characteristic. Cronbach stimulated research in this area in earlier publications suggesting that ATI research was an ideal ...