<![CDATA[This research aims at improving activeness and mathemathics learning achievement through cooperative learning model ; Teams accelerated-instruction (TAI) type. The hypothesis of the action research is that cooperative learning model ; Teams accelerated-instruction type is able to improve activeness and mathemathics learning achievement on 7th grade students in SMP Negeri 3 Pengasih Kulon Progo at 2012/2013 academic year.  This research is Classroom Action Research using quasi-experiment method conducted at least in two cycles. The subject of the research is 32 students of class VII A in SMP Negeri 3 Pengasih Kulon progo while the research object is mathematics learning process through cooperative learning model ; Teams accelerated-instruction type intended to know the degree of srudents’ activeness and mathemathics learning achievement in SMP Negeri 3 Pengasih Kulon Progo. Data collection techniques in the research are observation sheets, documentation and field notes. The instruments used are observation sheets and achievement test. The instrument try-out is validity and reliability test. The result of the research shows that after being applied cooperative learning model ; Teams accelerated-instruction type in the classroom, the students’ activeness and mathemathics learning achievement is improving. The improvement is indicated that there is an increased percentage average on observation sheets of mathemathics learning achievement in each cycle. The first cycle’s increased average is 49,61% categorized as moderate level and the second one is 69,33% categorized as high level. Seen from the average of students’ mathemathics learning achievement, there is also improvement. The average of the students’ prior knowledge related to mathemathics learning achievement is 65,63 fulfiled 53,12 % Minimum Crietria of learning Mastery (17 students). The first cycle shows that the average of the students’ mathemathics learning achievement is 70,09 fulfiled 59,38 % Minimum Crietria of learning Mastery (19 students). The second cycle shows that the average of the students’ mathemathics learning achievement is 79,18 fulfiled 71,9 % Minimum Crietria of learning Mastery (23 students). Accordingly , it is recommended for mathematics teachers to apply cooperative learning model ; Teams accelerated-instruction type to solve the problems emerged in the learning process.]]>
