Starting from Perkins’ (1985) framework, this study addresses tool use in a computerbased learning environment. In line with Perkins, first the effects of tool use on performance were investigated to gain insight into the functionality of the tools. Next, the influence of advice was studied to identify whether this advice could make students more knowledgeable with respect to the tools, and hence encourage them to make more (adequate) use of the tools. A third research question addressed learner related variables. The influence of metacognitive skills, goal orientation, and instructional conceptions on students’ tool use was investigated. An experimental design was used to address these research questions with one control group and two experimental groups, one with advice and one without advice. Results reveal that the tools were functional, the two experimental groups outperformed the control group. With respect to advice, the group of students receiving advice used tools more frequently and spent more time on their use. Finally, the study reveals mastery orientation to be an important variable. The more students are mastery oriented, the less they use tools.