Helping students to stay motivated by creating an environment that makes them interact is essential to attaining academic achievement. This action research utilizing mixed methods approach explores the flipped classroom's impact on the students' achievement motivation. Also, a significant focus has been on how students interacted with their classmates, the teacher, and the content. The online course management MyOpenMath was utilized in the first cycle of the study. Descriptive statistics was utilized in the study to analyze the results of the adapted Four Dimensions of Achievement Motivation, Flanders' Interaction Analysis Matrix, and students' Chapter Test grades for academic achievement. Observations by the department chair were utilized to establish themes. It is through concurrent triangulation that the researcher understood convergence, differences, and combination of data. The data show that there is a significant improvement in students' achievement motivation except in the strive dimension. Class observation analysis revealed less teacher talk, more pupil talk, and slight increase in silence or confusion. None of the students failed in their Chapter Test. The Analyze-State-Select-Utilize-Require-Evaluate (ASSURE) model was deemed to best fit the guiding principles in Algebra 2/Trigonometry course delivery based on the study's results.