A weblog (blog or Web log) has recently become one of the most widely used Internet applications. The current study concerns developing a blog specifically designed for learners learning English as a foreign language. The study investigated the effects of extensive writing by comparing the writing performance in the first three and the last three blog entries written by the participants. The study also conducted a survey to examine participants' blogging process and their perception of blogging. The results of the study show that writing on blogs could enhance participants' overall writing performance, promote participants' autonomous monitoring of their own writing, and promote positive attitudes toward foreign-language writing. From its findings, the study concluded that writing weblogs in an online environment could be beneficial in improving learners' writing skills, enhance learners' motivation to write, and foster both learners' monitoring strategies and learner autonomy. (Contains 9 tables and 2 figures.)