The paper presents the facilities offered by the open learner model maintained in the web-based, adaptive, activity-oriented learning environment SCALE (Supporting Collaboration and Adaptation in a Learning Environment), in order to guide online students who become disengaged and support their reengagement. The open learner model (OLM_SCALE) contains and represents information about students' performance level, the minimum, maximum, and average performance level calculated from all the students enrolled in the specific subject matter, and students' interactions with the system. The paper gives an outline of the SCALE environment and OLM_SCALE and presents an empirical study that was conducted. The results of the study revealed that: 1) students positively admitted the facilities of OLM_SCALE and 2) the exploitation of OLM_SCALE can effectively lead disengaged students to work in an engaged way. (Contains 6 tables and 4 figures.)