Students encounter many obstacles during scientific discovery learning with computer-based simulations. It is hypothesized that an effective type of support, that does not interfere with the scientific discovery learning process, should be delivered on a “just-in-time” base. This study explores the effect of facilitating access to knowledge and skills through just-in-time information. An experiment was conducted in which a group of students who worked with a computer simulation on geometrical optics had access to “information tips” during learning. Performance of this group was compared with that of a group who had no access to information tips. Results showed that the first group showed a better learning gain than the second group. The implications of the results are shortly discussed.