Erta Sri Wahyu^1,, Sahyar¹, Eva Marlina Ginting¹

This research aimed to analyze the gain of students’ critical thinking and problem solving ability by using conventional learning; to analyze whether the gain of students’ critical thinking and problem solving ability by using problem based learning model better than conventional learning. This research was a quasi experimental research with two group pretest-posttest design. The population of this research was second semester of State Senior High School 1 class X academic year 2016/2017.The sample of this research were two classes that consisted of 70 students by using cluster random sampling technique. Class X MIA-1 as experimental class taught by problem based learning model that consist of 34 students, class X MIA-2 as control class taught by conventional learning that consist of 36 students. The instruments of the research were essay test of critical thinking ability and problem solving ability that consist of 5 questions for each. The data were analyzed by using t-test statistics. The results showed that: the mean gain of students’ critical thinking and students’ problem solving ability taught by problem based learning was in medium level and the mean gain of students’ critical thinking and students’ problem solving ability taught by conventional learning was in low level. Hypothesis test showed that the mean gain of students’ critical thinking and problem solving ability taught by problem based learning was better than conventional learning, this result showed that there was an effect of problem-based learning model on students’ critical thinking and problem-solving ability.

problem based learning model, critical thinking ability, problem solving ability