IMPLEMENTATION OF PROBLEM BASED LEARNING MODEL TO IMPROVE STUDENT'S MATHEMATICAL PROBLEM SOLVING ABILITY OF XI GRADE IN SMA NEGERI 1 TEBING TINGGI

The aim of this research is to increase students’ mathematical problem solving ability through problem based learning model was done in SMA Negeri 1 Tebing Tinggi. The type of this research is Classroom Action Research. The research had done respect to the student of XI Science in 36 students. Instruments used to collect the data were mathematical problem solving ability test, observation sheet, interview, and quesioner. This research had done in two cycles which each cycle had two meetings and the end of each cycle was given mathematical problem solving ability test. Before given, at the first tests must be validity. Validity test done is contents validity where expert as validator. The result in this research had shown that learning by problem based learning model can increase students' mathematical problem solving ability. After given treatment, the result of the mathematical problem solving ability tests had 7.53% improvement, those are in cycle I the score got 62,5% (medium) and 70,03% (high) in cycle II