Marilou M. Saong, ChE, MS Mathematics
Constructivism specifies that the learner is an information constructor. Knowledge is constructed based on personal experiences and hypotheses of the environment. Teachers need to recognize that only the learner can choose to learn meaningfully and that learners will not be able to build new knowledge upon faulty prior knowledge. Thus, teachers must help students correct alternative conceptions and assist meaningful learning. It is therefore the objective of this study a) to evaluate freshmen Engineering students’ alternative conceptions about acids, bases, chemical equilibrium and electrochemistry as learned in high school or introductory college Chemistry b) to evaluate the impact of portfolio teaching in correcting alternative conceptions in selected topics in General and Inorganic Chemistry; and c) to determine the causes and sources of students’ alternative conceptions. The study employed a pretest-posttest control group quasi-experimental design involving two intact Engineering chemistry classes. The control group was taught using traditional lecture method while the experimental group was taught using portfolio teaching. Results of the pretest showed that students belonging to the experimental and control groups had a great number of misconceptions related to the concepts of acids, bases, chemical equilibrium and electrochemistry. Qualitative results revealed different sources of alternative conception including high school chemistry, internet and introductory college chemistry. Analysis of covariance results showed that the experimental group performed better in the posttest than the control group implying that portfolio teaching was effective in correcting alternative conceptions in acids, bases, chemical equilibrium and electrochemistry. Several recommendations have been made based on the results of the study.
Key words: Alternative conceptions, Portfolio teaching, Acids and bases, Chemical equilibrium, Electrochemistry
Source: UB Research Journal, Vol. XXXV, No. 1, January – June 2011