The focus of research problem was students' teamwork attitude and learning achievement. The study aimed to improve the students' attitude of teamwork and achievement through Student Teams Achievement Division (STAD) cooperative learning type on Lesson 9 Grade IV SD Negeri 2 Kecila. The research subjects were grade IV students, consisted of 21 students; 11 male and 10 female. The research instruments were observation sheets of teacher and student activities, teamwork attitude observation sheets and evaluation sheets. The results of Cycle I indicated that teamwork attitude obtained an average score of 1.80 or sufficient criteria, and it improved in the Cycle II into 3.08 for the average score or in good criteria. This improvement was also supported by the results of students' learning achievement, students gained an average of 53.3 with learning mastery of 14.3% of the total number of students in the initial condition, in Cycle I improved into 68.6 for the average and achieved learning mastery of 66.7%, Cycle II collected an average of 83 and achieved learning mastery of 90% from the whole students. The implementation of STAD cooperative learning models can improve students� teamwork attitude and achievement in lesson 9 of grade IV SD Negeri 2 Kecila. Teachers may use varied learning models in the class, one of which is the STAD cooperative model thus the learning becomes active and interactive for students.