Critical thinking ability of students' mathematical is a component that must be mastered by the student. Learn to think critically means using mental processes, such as attention, categorize, selection, and rate/decide. Critical thinking ability in giving proper guidance in thinking and working, and assist in determining the relationship between the material with more material. Critical thinking skills very needed in solving the problem/solution search, and task completion. But the fact is this ability have not developed well, even at the middle school students. Therefore, should the effort to implement an instructional model that is expected to help improve KBKM students in mathematics. This research applies the Interactive Learning Setting Cooperative Model (ILSC) as an alternative to learning that is expected to enhance these capabilities. The sample in this research is 68 students of class X MAN Model Gorontalo in Gorontalo. The hypothesis was tested at 5% significance level. The data were analysed by applying the mean, standard deviation, and n-Gain. The result shows that: (1) there is a difference achievement, the enhancement of KBKM, in experiment class and control class; (2) Learning with ILSC models better than Conventional method.