Critical thinking ability in solving triangle problems based on lesson study for learning community (LSLC)

Critical thinking is one of the important skills students must possess in 21st century education. This purpose of this research is to analyse the difference of students' critical thinking ability in learning with Discovery Learning model based on Lesson Study for Learning Community (LSLC) with class using conventional learning. This study applies mixed method, which combines qualitative and quantitative method. Qualitative method in this study is operative on developing instructional instrument with Discovery Learning mode based on LSLC. The quantitative methods in the study is applied in the form of quasy experimental design. The research result shows that (1) the instructional instrument; valid, practical and effective criteria (2) there is difference of critical ability of control class and experiment class. This is indicated by the significant influence of application of Discovery Learning model based on LSLC on students' critical thinking ability