Abstract: We have developed a system that supports for effectively carrying out collaborative learning activities in a large-scale class via online. It is expected that the system may provide relieving our care and expense for both receiving and delivering peer reviewed reports between students. The system works together closely with a leaning management system (LMS). Thus it provides as a module of an open source LMS, specifically, Moodle. The Moodle Workshop module is useful for our activities, but unfortunately has restraint in an input method of evaluation. It would be optimal to take various methods if we conduct to design a course with peer activities, and also a frank exchange of unrestrained criticism or comments so that we customize the peer assessment module to fit needs.