This study aimed to measure the effectiveness of a proposed program in developing practices and modifying beliefs of practitioner teachers about the flipped classroom. To this end, the author followed a true experimental design, wherein the experimental group received training through the proposed program, whereas the control group received none, and after the treatment the participants were invited to run a posttest. A total of 50 female students were selected randomly from the Department of Islamic Studies, Prince Sattam Bin Abdulaziz University. To measure the post-performance of the two groups, the author used an observation card and a scale of beliefs on the flipped classroom. The findings of the study revealed (a) statistically significant differences between the mean scores of the two groups on the observation card in favor of the experimental group, indicating a strong effect of the proposed program on developing the teachers' practices of the flipped classroom; (b) statistically significant differences between the mean scores of two groups on the scale of belief in favor of the experimental group, indicating a strong effect of the proposed program on modifying teachers' beliefs about the flipped class; and (c) a positive statistical correlation at 0.05 between the teachers' practices and beliefs about the flipped classroom.