Abstract:
Physics is an important subject because of the role it plays in the industrial, technological, and economic development of countries. Despite its importance, students’ perfonnance in physics in Isiolo County has generally been low. The unsatisfactory perfonnance could be due to low levels of motivation to leam physics and critical thinking skills. Teaching approaches have been cited as some of the factors that affect students’ motivation to leam and physics critical thinking skills. This study investigated the effects of the problem-based learning (PBL) approach on students‘ motivation to leam and acquire critical thinking skills in physics. The study employed Solomon‘s Four Non-Equivalent Control Group design. The target population was 640 form two students in public co-education secondary schools in Isiolo County. The accessible population comprised 265 form two students in public co- education schools in Isiolo Sub County. Simple random sampling technique was used to select four co-educational schools which participated in the study. Two of these schools were in the experimental group while the other two were in the control group. The sample size comprised 128 fonn two students from the 4 selected schools. Critical Thinking Skills Physics Test (CTSPT) and Leamer’s Motivation Questionnaire (LMQ) were used to collect data. Experts in Curriculum and Instruction, Egerton University, examined the content and face validity of the two instruments. The reliability coefficients of CTSPT and LMQ were estimated using the Kuder Richardson (KR) 20 formula and Cronbach Alpha method. The reliability coefficient of CTSPT was 0.741 while that of LMQ was 0.793. Data were analyzed with the aid of the Statistical Package for Social Science version 25. Frequencies and percentages were used to describe and summarize data while the Analysis of Variance (ANOVA) and t-test were used to test the hypotheses at (X = .05 level. The findings indicated that PBL led to increased motivation and acquisition of critical thinking skills by students in physics. However the increase in student’s motivation was not statistically significant’. These findings may be used by Physics teachers as reference material to improve leamers’ acquisition of physics critical thinking skills. The findings may also assist physics teacher trainers in strengthening their training programs by incorporating PBL in them. This may go a long way in equipping teacher trainees with pedagogical skills that can enable them to motivate and impart critical thinking skills to their leamers.
