International Journal of Academic and Applied Research (IJAAR)   Year: 2023 | Volume: 7 | Issue: 3 | Page No.: 31-44 Effect of Mind-Mapping Strategy on Senior Secondary School Chemistry Students' Academic Achievement and Critical Thinking Download PDF OMOSOR, Makaraba Ruth Abstract: This study examines the effects of a mind-mapping instructional strategy on senior secondary school chemistry students' academic achievement and critical thinking. Six hypotheses were formulated and analysed. A quasi-experimental, non-equivalent pre-test, post-test, control group design using a 2 x2 factorial design was adopted for the study. The population of this study comprises a total of 19,409 SS II students offering Chemistry in all the government-owned secondary schools in Delta State for the 2021/2022 session. A sample of 48 SS2 students was drawn from two secondary schools in Delta State. The purposive non-randomized sampling technique was used for the selection of the schools. The instruments that were used for the study were the Chemistry Achievement Test (CAT) and a questionnaire titled "Students' Critical Thinking Scale" (SCTS). The validity and reliability of the instruments were determined. The face and content of the instruments were determined. The reliability of the instruments was also determined and the internal consistency reliability coefficient obtained for the CAT and SCT were 0.87 and 0.89 respectively. The data collected were analyzed using independent t-test and ANCOVA at 0.05 level of significance. The findings of the study among other showed there is a significant difference in the mean achievement scores of students taught chemistry using the mind mapping instructional strategy and those taught using the conventional method. There is no significant difference in the mean achievement scores of male and female students taught chemistry using a mind-mapping instructional strategy; there is a significant difference between the critical thinking scores of students taught chemistry using a mind-mapping instructional strategy and those taught using the conventional method. In line with the findings of this study, it could be concluded that the use of mind mapping instructional strategy enhanced chemistry students' academic achievement and critical thinking better than the conventional method. Based on the findings of this study, it was recommended among others that in the classroom, chemistry teachers should aim to introduce students to mind mapping as an instructional method that promotes and encourages active engagement in learning, learning by doing, and learning by experience.