The competences of making good use of digital information and technology as well as making critical judgments and communicating with others have been considered as important educational objectives, in particular, for teacher education. Peer assessment is a frequently adopted learning strategy to assist students in rating and offering instant feedback to peers from the perspective of instructors, which has good potential for fostering students' critical thinking. However, the conventional peer-assessment approach mainly focuses on communications between reviewers and reviewees, while peer communications for collaboratively providing comments or suggestions are generally ignored. As a result, the present study proposed a Collaborative Feedback-based Peer-Assessment (CFPA) learning approach; moreover, a learning system was developed for evaluating the effectiveness of the different collaborative peer-assessment approaches by conducting a quasi-experiment in a pre-service teacher training program. Two classes of students participated in the experiment. One class including 48 students was the experimental group learning with the CFPA approach, while the other class with 49 students was the control group learning with the Non-Collaborative Peer Assessment (NCPA) approach. The findings indicated that the pre-service teachers who learned with the proposed approach showed significantly better instructional video development quality and commenting quality as well as higher self-efficacy and critical thinking tendency than those learning with the Non-Collaborative Peer Assessment approach.