More than one correlation coefficient can be computed between two variables when the data can be organized into subsets determined by one of more grouping factors. Implications of this fact are discussed when the variables are items and the correlations are being computed for purposes of scale development. (Author/

Presents an overview of some well-known instruments and recently developed scales for assessing student or teacher perceptions of actual or preferred classroom learning environments. Past research and practical applications followed using the instruments are described. (SM)