The paper reviews contributions of J. Piaget and others to the understanding of perception's importance in the cognitive development of mentally retarded children. The effects of poor discrimination learning on IQ scores are noted. (CL)

Reexamines the traditional role of observation in science and science education. Proposes that since observation is based on some view of the world, it is not innocent and unbiased, but theory-dependent. Discusses possible implications for the science curriculum when reconsidering the role and status of observation in science. (TW)