This study aimed at: (1) describing factors that influence the low mathematical problemsolving abilityand the average improvement of each indicator of mathematics problem solving ability;(2) finding out the effect of applying scaffolding technique in PBL model on mathematics problem solving ability. The subject of this study was grade VIII studentsat SMPN 5 Kendari. Qualitative and quantitative methodswere used in this study.The results of this study were: (1) factors that influence the low mathematical problem solving ability arethe studentsrarely trained questions which related to problem-solving and the learning model used by the teacher was not suitable for teaching mathematical problem solving. The average improvement of each indicator of mathematics problem solving ability by using PBL modeland DI model are: (a) understanding the problem 57.2 to 76.9 and 56.8 to 59.3; (b) solving problem 52.4 to 75.8 and 51.6 to 57.3; (c) answering problem 40.4 to 65.8 and 41.2 to 47.5; (2) studentswho were taught with PBL model have higher score than students who were taught with DI model, so there is an effect of the application of PBL model in improving mathematics problem solving ability of students of SMP 5 Kendari..
Keywords: Problem-Based Learning, mathematics problem solving, scaffolding technique
