This study examined the role of different goal-setting instructional interventions in facilitating students' shift to more sophisticated mental models of the circulatory system as indicated by both performance and process data. Researchers adopted the information processing model of self-regulated learning of P. Winne and colleagues (1998, 2001) and empirically tested the model by examining how students regulated their own learning when using a hypermedia environment to learn about the circulatory system. Undergraduate students (n=40) were randomly assigned to one of four goal-setting instructional conditions (co-regulation, strategy instruction, learner generated sub-goals, and bottom-up) and were trained to use a hypermedia environment. Pretest, posttest, transfer test, and verbal protocol data were collected using pretest-posttest comparison group design with a think-aloud methodology. Findings reveal that the co-regulation and strategy instruction conditions facilitated the shift in learners' mental models significantly more than the other conditions. Learners in the co-regulation condition benefitted by having the tutor co-regulate their learning by planning their goals, monitoring their emerging understanding, and providing scaffolding, using effective strategies, and providing motivational scaffolding. Learners in the strategy condition also made significant knowledge gains by regulated their learning differently since they did have the tutor to co-regulate their learning. Learners in the learner-generated subgoals and bottom-up conditions were less effective at regulating their learning and exhibited great variability in their ability to self-regulate their learning during the knowledge construction activity. Results provide a valuable initial characterization of self-regulated learning in a hypermdeia environment across several goal-setting instructional conditions. (Contains 4 tables and 40 references.) (Author/SLD)