This research aims to (1) identify whether Student Team- Achievement Divisions (STAD) can improve students’ writing skill; (2) describe the students’ motivation when Student- Team Achievement Divisions (STAD) is implemented in English lesson.
This action research was held at SMP Negeri 6 Sragen for 31 students of class 8E. It was conducted in two cycles where every cycle consisted of four stages: planning, acting, observing, and reflecting. The technique of collecting data is divided into two: qualitative and quantitative. In qualitative, the data were collected by observation, interview, questionnaire, and diary.While, quantitative data were collected by test.
The result of the research proves that (1)The use of Student-Team Achievement Divisions (STAD) can improve students’ writing skill. The improvement can be seen from their writing test mean score that increased. The students’mean score in pre-test was 70.79, then it improved to 76.00 in cycle 1 and 81.45 in cycle 2. (2) The use of Student-Team Achievement Divisions (STAD) can improve students’ motivation in English lesson. The improvement can be seen by some indicators: (1) students were more active to answer teacher’s question and did not complain about the task given, (2) students tried their best to do the quiz, volunteered themselves to explain their understanding, and had confidence to face the task, (3) they immediately did the task after the teacher gave it to them, and had a pleasure to do it, (4) students more concentrated to the lesson, (5) students were paying attention about the detail of the material better, (6) students did not hesitate to ask the teacher when they did not know about the certain material, and (7)  students ignored their friends when they invited them to improper conversation.
STAD is an alternative way for the students and teacher to gain benefits in English lesson, especially to improve writing skill and their motivation. It can be a good recommendation for the teacher who want an effective and interesting method in teaching English