Effect of Flipped Classroom Instructional Strategy on Students’ Achievement in Basic Science in Nigeria

Background: The flipped classroom may improve science learning by moving initial content exposure outside class and using classroom time for guided and collaborative activities. This study examined its association with achievement, retention, and interest in Basic Science among Junior Secondary School Two students in Delta Central Senatorial District, Delta State, Nigeria. Methods: A quasi-experimental pre-test, post-test, non-equivalent control-group design was used. The sample comprised 292 students from six mixed public secondary schools, with 146 students in the flipped-classroom group and 146 in the lecture group. Data were collected using the Basic Science Achievement Test, Basic Science Retention Test, and Basic Science Interest Inventory. Means and standard deviations were used for descriptive analysis, while independent-samples t-tests were used to compare post-intervention scores at the 0.05 significance level. Results: The flipped-classroom group recorded a higher post-test achievement mean than the lecture group (68.72 versus 58.41). Its mean retention score was also higher (66.85 versus 54.72). For interest, post-intervention means were 74.38 and 60.84, respectively. The submitted analyses reported statistically significant differences for achievement, retention, and interest, with p-values below 0.001. Conclusion: The flipped-classroom strategy was associated with higher achievement, retention, and interest scores in this sample. Interpretation should remain cautious because intact groups were used, school-level clustering was not addressed, and intervention delivery, instrument reliability, and the retention interval were incompletely reported.