This article describes the development and implementation of an Internet-based educational system called Communicative Collection Assisting System (CoCoA) designed to assist student-centered instructing and learning for foreign students in learning Japanese written composition. CoCoA realizes communicative correction by exchanging marked-up documents via Internet. We studied exchange of corrected compositions, using Communicative Correction Mark-up Language, a set of mark-up conventions used for encoding text. We proposed an effective method for finding out writing errors in the revised text, With this method, when the teacher completed the correction of a student's composition, CoCoA system call find and analyze the writing errors that exist the student's composition, and create an error profile for the composition in certain types of Japanese morphological errors. The error profile can be used to choose the materials with similar type of morphological errors for the student's correcting exercise, and to help the teacher for understanding the student's weaknesses. On viewing the results of experimentation, the CoCoA system can be used in the corrections of foreign students' compositions, and the instructions of foreign students' writing of Japanese compositions. (C) 2000 Elsevier Science Ltd. All rights reserved.