Low knowledge of mathematics can have an impact on the quality of education so that the importance of knowledge of mathematics is assessed and designed properly in learning both in terms of planning and preparation in teaching because learning that is planned beforehand will be more focused. Lesson study based learning for the learning community prioritizes several indicators including community learning, collaborative learning, caring community and jumping tasks which make children more willing to learn together and there is an attitude of tolerance among students. The research uses the mix method method with the development of thiagardjan through the 4D realm, namely define, design, develop and desseminate in experimental research using a nonequivalent control design with the results obtained from the pretest value to determine prior knowledge and posttest to determine knowledge after being given treatment and conducting interviews as research supporting analysis materials. The results showed that the development of the deviceLearning Development based on Lesson Study For Learning Community in increasing motivation to learn mathematics significant increase significant effect Based on the data correlation results (r) = 0.644 with the number of respondents 61 students. The correlation value (0.644) is in the interpretation value between 0.40 to 0.70, this shows that the relationship between students' learning motivation and learning tools using lesson study for learning community is moderate or quite strong.

Keywordss: Education; Lesson Study For Learning Community; Motivation