This study aimed at investigating the effect of flipped classroom strategy on the academic achievement in the subject of science among fourth grade students in Jordan. The study population consists of all fourth grade students in the Directorate of Private Education in Amman area, totaling 2134 students during the second semester of the academic year 2015-2016. The study sample consists of 44 male and female students who were chosen purposely from the study population. The study sample was distributed into two groups: the experimental group that consisted of 22 students, who has studied according to flipped classroom strategy, and the control group that consisted of 22 students, who has studied in the ordinary method. To achieve the objectives of the study, an achievement test was prepared and its validity and reliability were checked. ANCOVA, Means, and Standard Deviations were used to analyze the collected research data. The study deduced the following results: 1) There are statistically significant differences in the Means on the educational achievement test attributed to the teaching strategy, in favor of the members of the experimental group, and 2) there are no statistically significant differences in the Means on the academic achievement test attributed to gender. In light of the findings, the study recommended encouraging science teachers to teach students using teaching strategies emanated from the use of modern technologies, particularly the flipped classroom strategy. In addition, the study suggested that colleges of education should train prospective teachers on the use of teaching strategies stemming from modern educational theories and strategies such as the flipped classroom strategy during the period of preparing them to teach. Furthermore, the study recommended re-applying this experience and identifying its effectiveness at other schools stages and other subjects in other content areas.