Analyzed the laughing and smiling behaviors of 12 retarded students (mean CA 14 yrs 11 mo; Peabody Picture Vocabulary Test mean MA 4 yrs 9 mo) during usual classroom activities and while watching 3 cartoons on a video screen. Responses correlated with MA and the teacher's prediction of student responses in both situations. Such observational analysis is important for developing leisure and curriculum material for the retarded. (7 ref) (PsycINFO Database Record (c) 2004 APA, all rights reserved)