The prediction by 13 elementary school teachers of 214 students' achievement in Grades 4 to 6 on the Gates-MacGinitie Reading Test, Level D was examined. Although teachers were generally good predictors of students' achievement in reading, predictions were affected by various factors related to students and teachers. Female teachers, but not male teachers, tended to overestimate the number of correct responses by girls and underestimate that by boys. A similar trend was evident for inexperienced teachers. When they overestimated, male teachers and inexperienced teachers tended to overestimate more.