The type of this research is descriptive research with qualitative approach. This research was done in class of VII-A SMPN 2 Balongbendo in second semester 2018/2019. There are thirty three students in that class. The data of students learning interaction were got from observation sheet and note and students’ constructive attitudes were got from questionnaire. Based on data analysis can be concluded that the interaction of students Mathematics learning in cooperative learning in case of delivering idea or opinion is 53, 8% for first group and 46, 7% for second group. In case of giving a help with some explanations is 15, 4% for first group and 20, 0% for second group. In case of giving a help without some explanations is 15, 4% for first group and 13, 3% for second group. In case of asking a help is 15, 4% for first group and 20, 0% for second group. Students’ constructive attitudes by using STAD type of cooperative learning show that most of students have quite good constructive attitudes about Mathematics that is twenty four of thirty three students.