The population of this meta-analysis were the available related studies done between 1370-1392 in the country, including full-text articles, theses and research projects in the databases and libraries, universities or government agencies. Based on the inclusion exclusion criteria as well as sensitivity analysis, almost 323 effect size from about researches were investigated. The results of the combined effects of gender differences on the effectiveness of cooperative and discussion methods in random model for girls and boys was 0.665 and 0.589, respectively, which were both statistically significant effect sizes. Based on Cohen's criteria, we can say that the effectiveness of these methods for male and female students is average and desirable. Also, the independent t-test results showed that there is no statistically significant difference between the effect size means of boys and girls although the effect size for girls was greater. So, as suggested by the theoretical foundations of these teaching methods, these methods are not limited to a particular ability level or sex but all who are engaged in can benefit from these methods