Summary: This article describes a triarchic analysis of an aptitude-treatment interaction in a college-level introductory-psychology course given to selected high-school students. Of the 326 total participants, 199 were selected to be high in analytical, creative, or practical abilities, or in all three abilities, or in none of the three abilities. The selected students were placed in a course that either well matched or did not match their pattern of analytical, creative, and practical abilities. All students were assessed for memory, analytical, creative, and practical achievement. The data showed an aptitude-treatment interaction between students' varied ability patterns and the match or mismatch of these abilities to the different instructional groups.
