The Melbourne International School of Japanese (MISJ) is a supplementary Saturday school which offers Japanese language and mathematics taught in Japanese from kindergarten to senior secondary level. Classes are scheduled on Saturdays from 9am to 3pm and approximately half of the program is dedicated to mathematics. While mathematics education aims at developing both numeracy and Japanese language skills, many students struggle to understand mathematical concepts. Furthermore, the students have difficulties in solving worded mathematical problems due to poor command of Japanese. This lack of Japanese language competency is, thus, a significant issue for the students. In order to address this situation, one primary teacher and one secondary teacher attempted several strategies in mathematics teaching, incorporating strategies typical of second language teaching. The primary school teacher integrated teacher talk with the use of visual aids including video clips to assist the students' understanding of mathematical concepts. The secondary teacher employed vocabulary cards, so that the students would pay attention to key words in order to be able to comprehend mathematical concepts in Japanese effectively. Although both teachers incorporated these strategies, some students still had difficulty in understanding mathematical concepts because of their lack of cognitive academic language proficiency (CALP) (Cummins, 1996).