Writing is one the most rewarding areas of teaching for teachers of EFL because in this area, students can often show greater and faster improvement than in any other English skill. Of course, language acquisition itself is a slow and gradual process even in writing. However, language is only one measure of good academic writing. Other factors, such as focus, organization, elaboration, and coherence, are also essential, and it is in these skills that we can expect substantial improvement of the students. Over the years of teaching English paragraph writing to Japanese students, I came to notice the pedagogical value of the topic sentence in teaching the above skills. This article shows the results of a semester course that taught paragraph writing with special attention to the topic sentence, and tries to propose one way of teaching English writing that could bring positive result.