ABSTRACT

 The aim of this study was to integrate the results of the findings of previous research studies on effect of concept mapping on students' academic achievement and retention in sciences so as to arrive at a conclusive end point (effect size). The study adopted expost facto research design through meta-analytic procedure. The population of the study consisted of 112 reviewed published and unpublished previous research reports on effect of concept mapping on students' academic achievement and retention in sciences in Nigeria. A sample of 97 independent research reports from the primary studies on effect of concept mapping on students' academic achievement and retention in sciences carried out in Nigeria from 2000-2018 were purposively drawn and used for this study. This sample is made up of 73 reports on achievement and 24 reports on retention in sciences. The data was collected using a coding instrument which was designed for this study. The reliability of the instrument was found to be 0.84 using inter-rater agreement reliability. Percentages, statistical transformations and effect sizes were used to analyze the data for the research questions while the winer combined test was used to test the hypotheses at 0.05 levels of significance. The findings of the study showed among others that the results of the previous studies on effect of concept mapping on students' academic achievement in sciences are positively significant at 0.05 levels. The results of the previous studies on effect of concept mapping on students' retention in sciences are positively significant at 0.05 levels. The mean effect sizes for the 73 studies examined under achievement on effect of concept mapping on students' academic achievement in science recorded a positive and large effect size (0.605). The mean effect size for all the 38 studies on gender recorded a positive and moderate effect size (0.295). The mean effect sizes for the 24 studies examined under retention on effect of concept mapping on students' retention in sciences recorded positive and moderate effect size (0.475). The mean effect size of studies on effect of concept mapping on students' academic. achievement in science was significant at 0.05 levels of significant. There was significant variation of effect sizes of the studies examined based on gender at 0.05 level of significant. There was significant variation on effect sizes of the studies on effect of concept mapping on students' retention in science at 0.05 levels of significant. Based on the findings of the study, it was recommended among others that curriculum of teacher training institutions should be broad enough in the special method courses to include and give enough time for teaching principles underline the use of concept mapping in teaching sciences since it enhance students achievement and retention in science; government through the ministry of education and professional bodies like Science Teachers Association of Nigeria (STAN) and Association of Educational Researchers and Evaluators of Nigeria (ASSEREN) should provide in-service training, workshops, seminars and conferences for science teachers on the teaching of sciences using concept mapping.