E-ISSN: 2476-9606 Abstract Proceedings International Scholars Conference Volume 7 Issue 1, October 2019, pp. 1539-1549 https://doi.org/10.35974/isc.v7i1.1161 1539 Enhancement of Junior High School Students Problem Solving Ability Using Missoury Mathematics Project Learning Model with Individual and Small Group Assignments Joy Frandero Pasaribu 1 , Louise M. Saija 2 Universitas Advent Indonesia louise.saija@unai.edu ABSTRACT Mathematical problem solving ability is very important since it can help students to solve their daily problems. Studies shows that most of students only wants to know the standard procedures when they learn mathematics, and tends to give up when the given problems are different. This comparative study aims to know the students mathematical problem solving enhancements, and whether there is significant difference between two groups of students which acquire Missoury Mathematics Project learning model with individual or small group assignments. Samples for this research are junior high school students from SMP Advent II Bandung, grade seven. The instruments used in this research are mathematical problem solving test and quesionaire of responses. The research result shows that the mathematical problem solving enhancement categorized as high1. And there is a significant difference between those two groups of students which acquire Missoury Mathematics Project learning model with individual or small group assignments2. While the result from the quesionaire of responses shows that students like the Missoury Mathematics Project learning model. Keywords: Mathematical Problem Solving Ability, Missoury Mathematics Project. INTRODUCTION Mathematics is one of the universal subject which has an important role in the development of human thinking power, and is a science that is able to integrate with other subjects and real life (Rostika & Junita, 2017). From a course of learning we are expected to not only be able to master the material, but can use the knowledge in dealing with problems to achieve an achievement and be able to apply it in every course of learning. National Council of teachear of Mathematics (NCTM) stated that mathematics learning includes five abilities, that are: 1. mathematical communication 2. mathematical reasoning