The internal/external frame of reference (I/E) model (Marsh, 1986) posits that the effects of contrasting math and verbal domains of achievement are positive for matching academic self-concepts (ASCs) but negative for nonmatching ASCs (i.e., math achievement on verbal ASC; verbal achievement on math ASC). We extend the classic I/E model by contrasting the math domain with 2 verbal domains (Chinese, native language; English, foreign language) in combination with language of instruction (English or Chinese) for a sample of 1,950 Hong Kong Year 7 students. Consistent with predictions based on the Marsh and Shavelson (1985) ASC model and our extension of the I/E model, we found that native and foreign languages were not contrasted with each other in the formation of ASCs. However, achievement in both verbal domains negatively predicted math ASC, while math achievement was also negatively predicted by ASCs in both verbal domains. Support for the predictions was similar for students taught in English and Chinese languages of instruction. (Contains 4 figures and 1 table.)