The purpose of this study?

The purpose of this study was to determine the effect of Problem Based Learning (PBL) on students' higher-order thinking abilities in mathematics learning. This research is library literature so the data collection method used is documentation, which is tracking written sources that contain various themes and topics discussed. The model used in this study is a synchronous research model. This will be done by looking at and linking the characteristics and indicators of students' high-level thinking skills in mathematics learning with the characteristics of the Problem Based Learning (PBL) model. From the results of data analysis it can be concluded that there is an influence of Problem Based Learning (PBL) on the level of thinking ability student height on learning mathematics.

INTRODUCTION Mathematics is an important subject, there are many activities related to mathematics. Mathematics is one of the subjects given from basic education to higher education. The objectives of learning mathematics, such as: "(1) understanding mathematical concepts, explaining the relationship between concepts and applying concepts or algorithms flexibly, accurately, efficiently and steadily, (2) using reasoning in patterns and properties, performing mathematical manipulations in making generalizations, proofs compile or explain mathematical ideas and achievements, (3) problem solving which includes the ability to understand problems, design mathematical models, solve models and find solutions (in Astriani, Surya, and Syahputa, 2017). Based on the objectives of mathematics learning above, mathematics learning requires students to be able to improve student problem solving ranging from simple levels to higher problem solving.This shows that the ability of problem solving is a competency that is very important to be developed in students in learning mathematics, this is because also in learning mathematics requires the ability to t is high so students are able to solve mathematical problems and are able to apply them in today's life that is not free from mathematical challenges and problems.

In learning with the 2013 curriculum that is based on student-centered learning increasingly requires students to be able to the point of creating. To achieve this requires the ability of teachers to innovate in learning so that they are able to train students to think at a high level to solve problems and find solutions to be able to create something new. Also in the 2013 curriculum, learning uses scientific methods, multi-strategy, multimedia, adequate learning resources and technology, and utilizes the environment as a learning resource. The right learning model used is problem based learning. This model is appropriate for improving mathematical problem solving skills