In this study we investigated the effects of teaching thinking skills on academic achievement and reading comprehension in grade 7 students. For this means, numbers of students (N=83) both girls (N=44) and boys (N=39) were sampled from area 1 and 6 of ministry of education in Tehran. All students had low academic achievement (mean of basic lessons equal or below 15 points). Their half term exam (Dec 2002) and final exam (Apr 2003) were served as index of their academic achievement. Also by the means of testing their reading comprehension, a test was designed. Students were divided in to experimental (N=42) and control (N=41) groups randomly. Thinking skills (Bono's Method) were taught to students in treatment group for 30 sessions. Whereas control group did not received such training. Results showed that there were no significant differences between treatment and control group in both academic achievement and reading comprehension. Findings were discussed in chapter five.