A study gauged the effects of peer tutoring on the reading skills of first graders. Subjects were 250 children divided into eight experimental and four control classrooms in a school district in Utah. Teachers were trained by researchers, bearing in mind five procedural principles: (1) appropriate modeling by the teacher, (2) extensive dialogue, (3) guided practice, (4) systematic mastery checking, and (5) systematic review. The program involved a series of "learning cycles" composed of exercises based on the content areas of sight words, letter sounds, blending, decoding, and oral reading. Students were paired according to achievement, highest with lowest and so on. Pair members tutored each other for half an activity and then reversed roles. Oral reading took place in several settings. Parental involvement was also encouraged. Tests given 8 months after the beginning of the program showed significantly higher levels of performance on early reading skills in the experimental group. This approach seems effective in helping teachers bring a large proportion of their students to the level of mastery. (JL)