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The purpose of this research is the effect of Schwab’s invitation to inquiry method and flipping problem solving on the academic function on Biology course of students of tenth grade with modifying critical thinking.This research’s method is semi – experimental with pre – test and post – test and control group.  Its statistical community includes female students of tenth grade of Tabriz city at the academic years of 2015-2016.Sample size consists of 69students of tenth grade were chosen by multistage cluster sampling methodGathering information tools include Ricketts critical thinking questionnaire and teacher made academic achievement test on Biology course.Data were analyze by covariance analysis method..The results indicated, critical thinking could be able act as a mediator in the effect of Schwab’s invitation to inquiry method on achievement of students werethought by Schwab’s invitation to inquiry method. In the other way it couldn’t act as a mediator in flipping problem solving