In foreign language learning, the importance of the amount of learner's exposure to the target language has been increasingly emphasized. One of the ways to ensure an ample amount of exposure is through extensive reading programs. However, little research has been done as to the possible effects of those programs on students' curriculum-based achievement. The project reported here is part of our efforts to prove positive effects on the learner's curriculum-based achievement. Kanatani et al. (1990, 1991), which investigated the effects of senior high school reading programs, proved that participation in the 3-4 week reading program played a positive role in the development of reading ability and that the effect became salient after a latent period of approximately 6 months. They also revealed the enduring effect of the reading program that continuously made a larger difference in reading ability between the participants and the non-participants. This present article attempts to prove whether the same type of effects can be observable with the junior high school participants of the program. It also aims at examining whether participation will bring about any changes in the participants' learning strategy and attitudes toward learning of English.