This study aims to investigate the impact of the flipped classroom (FC) on students' grammatical competence. To achieve that, a mixed-methods approach was adopted using a quasi-experimental research design to examine the differences between a control (n=20) and an experimental group (n=20) from two different high schools based in Morocco. The control group was taught by the author using computer-assisted instruction, while the experimental group was taught by a teacher using FC methodology. A post-test was used to test the two groups as well as interviews with a randomized sample of students from the experimental group. The findings suggest differences in favor of the treatment group, but the results were not statistically significant. While the interviews indicated high satisfaction with FC because it gave students opportunity for more interactions with teachers and peers, it also made students autonomous and fully engaged in the classroom activities.