Based on data collected from middle school students in a U.S. school (N = 159) and a Chinese school (N = 183), this study compared Internet use in school and at home between American students and Chinese students, explored what affected students' use of the Internet, and examined how students' Internet use related to their learning. Results reveal that (a) significant differences in online activities between American students and Chinese students were found in school, but not at home. Further analysis suggests that different pedagogical practices in these two cultural contexts led to the different uses of the Internet in school between American students and Chinese students. (b) There were significant school/home differences in Internet use for American students, but not much school/home difference was found for Chinese students. (c) There were salient similarities between American students and Chinese students in terms of the most popular activities they engaged in online. (d) Internet use in teaching and learning in school had some influence on students' interest in learning specific subjects. (Contains 3 tables and 1 figure.)