Using Exemplary Materials to Enhance students' Performance and Retention in Hybridisation

This study examined how exemplary materials improve students' performance and retention in hybridisation. A quasi-experimental pretest-posttest-post-posttest non-equivalent design was used with a modified Solomon four-group design, using hybridisation conception achievement tests (HCATs). A multistage sampling technique was used to sample four intact chemistry classes from four senior high schools in Kwabre East, Ashanti, Ghana, who had not been exposed to hybridisation. The control and experimental groups had two classes each. The experimental group learnt with exemplary materials in the form of models, balloons, and computer simulations. Data were analysed with SPSS 20.0. No pretest sensitization was observed, as no statistically significant differences were found between the posttest scores of the pretested experimental group and those not pretested (p = 0.07) and the posttest scores of the pretested control groups and those without pretest (p = 0.06). The posttest findings showed a significant increase in performance (p < 0.001) of the experimental group a week after the treatment. Experimental groups significantly performed better than control groups (p < 0.001). The experimental groups’ retention significantly increased three weeks after the posttest (p = 0.03). Again, experimental groups’ retention was better than the control (p < 0.001). Learning chemistry (and science) should involve using exemplary materials and student-centred pedagogies to improve the performance and memory of chemical concepts like hybridisation.