This study examined whether direct communication with people from other countries using Skype or Line would affect students' English test scores in listening and reading as well as the development of their curiosity concerning foreign cultures by comparing the data of an experimental group with that of a control group. The former group conducted online exchanges with foreign students, while the latter group did not. As many Japanese companies engaged in international business require high scores in the TOEIC test, which is one of the multiple-choice English tests of listening and reading often used to show each person's English proficiency, universities in Japan are making efforts to improve their students' scores in such an English test. Preparation classes for English tests have been offered. However, students have been likely to lose interest in learning English in the circumstances of this learning style. Results of the study indicated that although the aim of exchange activities is to foster students' curiosity concerning intercultural matters, students experiencing online exchange with skype significantly raised their scores in TOEIC tests in listening and reading after a programme of synchronous exchanges with foreign students, compared with ones who did not experience such online exchanges.