DEVELOPMENT IN MATHEMATICAL PROBLEM SOLVING SKILL AND LEARNING ACHIEVEMENT OF GRADE 8 STUDENTS ON THE APPLICATION OF RATIO AND PERCENTAGE THROUGH PROBLEM-BASED LEARNING OF POLYA’S PROBLEM SOLVING PROCESS

Abstract

The objectives of this research were as follows: 1) to develop mathematical problem solving skill of grade 8 students on the application of ratio and percentage in order that the students made an achievement score of 70% or higher in mathematical problem solving skill and at least 70% of the students passed the criterion; 2) to develop mathematical learning achievement of grade 8 students on the application of ratio and percentage in order that they made a mean achievement score of 70% or higher and at least 70% of the students  passed the criterion. The target group consisted of 23 grade 8 students studying in the first semester of 2020 academic year at Patcharagitiyapa Secondary School I in Nakhon Phanom Province under the Office of Secondary Education Service Area 22.   The study employed the primary experiment model in the type of the One-Group Posttest Only. The tools used for development assessment of the learners included: 1) 13 lesson plans using Problem-Based Learning and enhanced by Polya’s Problem Solving Process on the application of ratio and percentage that took 13 hours; 2) a subjective test for assessing the students’ mathematical problem-solving process skill with methods in finding answers; and 3) a 30 item, 4 multiple-choice test to measure the students’ learning achievement in the application of ratio and percentage. The collected data were analyzed by arithmetic mean, standard deviation and percentage.  Findings of this research were as follows: 1) For the results of mathematical problem solving skill, it was found that the students made a mean achievement score of mathematical problem solving skill at 83.03% and 23 students or 100% of the group passed the criterion of 70% that was higher than the prescribed criterion. 2) For the results of learning achievement development, it was found that students made a mean score of 26.59 or 88.63% of the full marks and 20 students or 86.95% of the group passed the criterion that was higher than the prescribed criterion.