The purpose of this study was to investigate the effect of cognitive strategies instruction on students’ attitude toward learning and academic functioning of science. This research method was semi-experimental with pretest, post-test, experimental and control groups. The statistical population consisted of all boys of grade 3 in Lordegan city. The samples were 126 students, who were selected with cluster sampling method, and then 64 students were randomly set in the experimental group and 62 in control one. The experimental group had seven sessions of cognitive strategies. The results of covariance analysis showed that cognitive strategies instruction has a positive effect on academic functioning of science. Also, attitude toward learning has been increased through cognitive strategies instruction.