posttest 4133332004 shown objective average iii teacher quite very correlation OF outcome education amount dahlena teaching feasible taught VII quality JUNIOR science result keyword student wa given SCHOOL need analysi validated learning medan research aspect expert positive development elaboration don manual variou REACTION during using grade higher valid ABSTRACT obtained obtain pulungan chemistry MANUAL done questionnaire equal LAB odd ON lab national understanding GRADE influence SCIENCE lecturer validator revision but ha based developed BSNP school chemical CHEMICAL effectivenes data LEARNING reaction consist agency assessment use junior SMP criteria belonging mean semester respondent DEVELOPMENT HIGH material standard pretest high overall