IMPLEMENTATION NUMBERED HEADS TOGETHER (NHT) TYPE OF COOPERATIVE LEARNING MODEL TO IMPROVE STUDENTS MATHEMATICAL LEARNING ACHIEVEMENT AT GRADE VIII SMPN 2 PORSEA ACADEMIC YEAR 2014/2015

Objectives of this research are: (1) To know how Numbered Heads Together type of cooperative learning model can improve students mathematical learning achievement, (2) To know the effectiveness of Numbered Heads Together type of cooperative learning model to students mathematical learning achievement, and (3) To know response that given by students to mathematics learning after implementation Numbered Heads Together type of cooperative learning model. This research include to Class Action Research (CAR) that was conducted in SMP N 2 Porsea. The subject of this research is all of students in VIII-1 class academic year 2014/2015 with number of students as many as 24 students that consist of 20 females and 4 males. Object of this research is students mathematical learning achievement and Numbered Heads Together type of cooperative learning model. The research was conduct in two cycles, cycle I consists of two meetings and cycle II consists of two meetings. The mathematical learning achievement test was conduct in the end of cycle. The research result can be seen as follows: (1) The result of students mathematical learning achievement test in cycle I: the average score was 67.71, there were 15 students got score greater than or equal to 65, 9 students got score less than 65, and classical learning mastery was 62,50%. (2) Implementation Numbered Heads Together type of cooperative learning model to improve students mathematical learning achievement was effective, (3) Responses that given by students to mathematics learning after implementation Numbered Heads Together type of cooperative learning model was positive.