In 2007, the government of Indonesia issued a new concept of formal education called SBI or International Standard School. Some schools in Indonesia are now prepared for becoming a real international standard school. Therefore, there are schools called RSBI or Future International Standard School. SMP N 4 Pakem is one of the RSBI Schools in Yogyakarta Province. As an RSBI School, SMP N 4 Pakem applies bilingual concept in the teaching and learning activities, specifically for natural science subjects. This study aims to answer two problems. They are: 1) How is English used by the teachers in delivering natural science subjects. This study aims to answer two problems. They are: 1.) How is English used by the teachers in delivering natural science subjects to a 7th grade class of SMP N 4 Pakem?, 2) What is teachers‟ perception on the use of English in delivering natural science subjects?
This research is a survey study. The participants of this research are four teachers who teach natural science subjects in class 7D at SMP N 4 Pakem. In order to answer the first problem, classroom observations were conducted. For answering the second question, the researcher used in-depth interview.
The findings obtained from the classroom observations showed that there was no exact tendency regarding in which lesson sections the teachers normally used English in the bilingual classes. In fact, each teacher used English in different lesson sections. However, it was also found that teachers had similar patterns in using English for the materials in bilingual classes. There were found that the teachers produced some full English utterances without Indonesian translation. There were also found some English utterances which were directly translated into Indonesian. Besides, the researcher found that teachers combined English and Bahasa Indonesia in the same utterances.
Based on the interview, it was found that all the four teachers participating in this research had the same perception on the use of English in delivering natural science subjects. English in bilingual classes was perceived positively. It was believed that the use of English in teaching natural science subjects brought advantages both for the teachers and the students of the RSBI School. However, there were also some points that needed to be improved from the use of English in natural science subject classes in terms of the students and teachers‟ preparedness, the lacking of local reference books, as well as the real classroom practices.Labels: bilingual classes, natural science subjects, RSBI School, sections in a lesson