THE IMPLEMENTATION OF PROBLEM BASED LEARNING (PBL) MODEL INTEGRATED WITH STUDENT TEAM ACHIEVEMENT DIVISION (STAD) TO INCREASE STUDENTS OUTCOMES IN LEARNING BUFFER SOLUTION AT SENIOR HIGH SCHOOL CLASS XI ACADEMIC YEAR 2014/2015

The objectives of this research are (1) to investigate whether the student’s achievement taught by PBL model integrated with STAD is significant higher than taught by STAD (2) to investigate whether the student’s active character taught by PBL model integrated with STAD is significant higher than taught by STAD (3) to investigate whether the student’s teamwork character taught by PBL model integrated with STAD is significant higher than taught STAD (4) to investigate the significant correlation between student’s active and teamwork character with student’s achievement. Sample was chosen by purposive random sampling and taken 2 classes in SMA Negeri I Rantau Selatan. The experimental class I taught by PBL model integrated with STAD while the experimental class II taught by STAD. The instrument test that used were 20 items of multiple choice test, an observation sheet of student’s active character that has 4 indicators and an observation sheet of student’s teamwork character that has 6 indicators to observe the development of student’s character. Before conducting the research, the pretest was done in both of experimental classes. The data was tested by using homogeinity test and the result shows that the sample was homogenous. Then the research was conducting in both of class and the observer observ the student’s character using observation sheet of student’s active and teamwork character during the process of research. After conducting teaching-learning process, the posttest was done in both of class. The increasing of student’s achievement (gain) is experimental class I is 74% (high) while in experimental class II is 63% (medium). The hypothesis testing was tested by using Independent Sample T-test with one tailed t-test and for correlation was tested by using regression with linear in SPSS-16 for windows. The research result are (1) The student’s achievement that taught by PBL model integrated with STAD is significant higher than the student’s achievement that taught by STAD (Sig= 0.002) (2) Student’s active character that taught by PBL model integrated with STAD is significant higher than the student’s active character that taught by STAD (Sig= 0.022) (3) Student’s teamwork character that taught by PBL model integrated with STAD is significant higher than the student’s teamwork character that taught by STAD (Sig= 0.031) (4) There is significant correlation between student’s active and teamwork character with student’s achievement (Sig F Change for both of experimental class is = 0.00)