Abstract
This study intends to analyze the effects of problem-based learning on students’ attitude towards learning, critical thinking skills and achievement of 10th grade students in chemistry. In this experimental study the students of two intact groups of Govt. high school 79 SB Sargodha, were selected as experimental (N=35) and control group (N=28). The students of both the groups were arranged with respect to their pre-test scores into three subgroups; low, average and high achievers. This experiment was conducted for the period of two months using pre-test post-test control group design with non-equivalent groups. The tools developed for measuring the dependent variables were; “Problem Solving Ability Test in Chemistry” (PSATC) and “Achievement Test in Chemistry” (ATC), and “Attitude towards Learning Scale”. On the basis of results, it was concluded that the students who received treatment, performed better than the students of control group in problem solving ability tests and in the achievement test and were better in their critical thinking skills (understanding, analyzing, evaluation and synthesis). Comparison within the experimental group reflected that the performance of high and average achiever students was same, but better than the low achievers in problem solving ability tests and achievement test.