This classroom action research aimed to improve the students’competence of
mathematical communication and self-efficacy class VII D SMP Negeri 1
Rembang through cooperative leraning of student facilitator and explaining type
on SPLSV and PTLSV matter. The research method was coopwerative learning of
student facilitator and explaining type. The reseach was classroom action
research. The subject was 36 students of class VII D. The research consisted of
three cycle with two meeting in each cycle. The data collection tecniques were
test, questionnaire,andobservasion. The result showed that there was improvement
in the students’ ability of mathematical communication. In cycle I, the average
was 45,47 with fair criteria, in cycle II the average was 67,7 with well criteria, and
in cycle III the average was 84,01 with very well criteria. The students’ selfefficacy
was also improved. In cycle I, the average score was 3,2 with well
criteria, in cycle II the average was 3,3 with well criteria, in cycle III the average
was 3,4 with very well criteria. The conclutsion was that through cooperative
learning of student facilitator and explaining type can improve students’
competence of mathematical communication and self-efficacy class VII D SMP
Negeri 1 Rembang.