Collaborative project-based learning is well established as a component of several courses in higher education, since it seems to motivate students and make them active in the learning process. Collaborative Project-Based Learning methods are demanded so that tutors become able to intervene and guide the students in flexible ways: by encouraging them to develop independent solutions and also by keeping their efforts and activities targeted towards the lesson goals. Students, on the other hand, need to develop important skills in searching and analyzing information as well as in communication and time management. In this paper, we propose the design of a collaboration script, following the "Group Investigation method", to support the tutors and students of a collaborative project-based course on "DataBases". We implemented this script using a compound e-learning collaborative environment based on MOODLE and LAMS, which have provided tutors with several tools and methods to involve in the learning process. The evaluation of the students' projects and the comparison with the corresponding projects of the previous academic year showed a better level of collaboration and performance of the students but also proved that the learning environment offered the tutors a more efficient way to guide their students in Collaborative Project-Based Learning.