Abstract:
This research studied problem-based learning management on surface area and volume for grade 9 students of Marywitthaya School. Thepurposes of this research were 1) to create learning lesson plans using problem-based learning on surface area and volume for grade 9 students at Marywitthaya School, 2) to compare the learning achievement of students after receiving problem-based learning management with criterion (70%), and 3) to study the effectiveness index of students after receiving problem-based learning management. The target group of this research was 20 grade 9 students who voluntarily participated in the experiment of the academic year 2018, semester 2, Marywitthaya School, Prachinburi Province. The data were collected by 10 learning lesson plans using problem-based learning and learning achievement tests. With a consistency index (IOC) at 0.72 and the achievement test with p values between 0.29 - 0.76 and r between 0.20 - 0.57. The results showed that 1) the process efficient of lesson plans was 70.63/70.35, which agreed with the criterion 70/70, 2) the learning achievement score of students was 15.95 or percentage of 79.75, which was significantly higher than the criterion at 70% at the 0.01 level, and 3) the students effectiveness index was 0.60, which was higher than the criterion 0.50