Web-based peer assessment is a valuable way to cultivate active life-long learning in the modern era. This study proposed a peer-learning teaching approach that incorporates a web-based system, Tronclass, and the mechanisms of peer assessment and feedback in a financial market course to improve students' learning performances and motivation. Sixty-eight college students participated in the course during a semester. Results showed that the students demonstrated higher scores in the post-test than the pre-test in terms of financial markets knowledge test and financial planning report, though there was no significant improvement in learning motivation. The students provided feedback of higher quality in the final report and the quality aspects of first-person and specificity were found to predict student performances. These results indicated that the combination of a web-based tool with a peer-learning approach offers an alternative and meaningful approach to increase individuals' performance and attitudes.