USING SELF-ASSESSMENT TO EXPRESS STUDENTS CONCEPT MASTERY OF CELL IN BILINGUAL TEACHING IN 11 TH GRADE SCIENCE OF SMA N 1 SIDIKALANG

Teachers in RSBI schools tend to be reluctant to use English as their medium instruction in teaching and learning process. They assume that students will be difficult to understand the concept if the topic is delivered in English. That is one of the reasons why teachers do not use English in Biology teaching. However, students can evaluate themselves whether they understand or do not. Self-assessment is one of alternative assessments that can help teachers and students to express the students’ concept mastery of the topic which is delivered by using English. Therefore, this research aims to know the using of self-assessment to express students’ concept mastery of cell in bilingual teaching process for 11th Science-1 students of SMA Negeri 1 Sidikalang.
The population of this research is all 11th grade science students of SMA Negeri 1 Sidikalang who taught bilingually. The sample of this research is 11th Science-1 students which is determined purposively. The concept that is used by researcher is cell concept. The using of English in teaching process is increased gradually in four meetings. There are three instruments that were used in this research, self-assessment sheets, students’ concept mastery test of cell and Questionnaires. The research result shows that students who assessed themselves understand the concept tend to get high scores in students’ concept mastery test. The correlation analysis shows that coefficient between self-assessment (SA) points and students’ concept mastery (SCMT) points represent the weak correlation (raverge = 0,225). It means students that have good self-assessment also have good result of concept mastery test, altough it is found only for a small number of students. Students’ concept mastery that was expressed from SA point showed that students still can get the concept even it is served in English.