The effects of prior knowledge on miscues were examined by requiring 20 second-grade average to above average readers to read an expository passage orally. They were divided into two sample groups. The control group was asked to read the passage with no prior instruction. The experimental group was given prior instruction, which consisted of pre-reading with vocabulary and text discussion. The basic premise of the study was that fewer reading miscues would occur when readers were engaged in an analytic previewing activity before reading the specific text aloud. Findings suggest that children with high prior knowledge made fewer miscues than the children with no prior knowledge. It is recommended that students be given information to develop their schematic base before they are required to undertake the text being presented. Support for these conclusions is discussed. (Contains 66 references and 2 tables of data; an appendix contains a sample reading passage.) (Author/RS)