Collaborative writing is a task commonly used for learning and assessment in higher education. The complexity of this type of task requires special support for learning contents. Feedback can be used as a key element to improve students' learning and engagement. This paper presents and evaluates a teaching innovation that sought to design a model feedback system. In this innovation, 218 students and 4 teachers participated in a course on Educational Psychology in Teacher Training. Questionnaires were used to collect students' perceptions and their satisfaction ratings regarding the quality of feedback received from the teacher. The students' uses of feedback were also taken into account. Additionally, interviews were conducted with instructors. The main results highlight the relevance of integrating the essential characteristics of effective feedback, as well as the use of ICT, for supporting learning in this complex task.