Especially in the context of technology-enhanced informal learning, it is crucial to understand how to design information sources in such a way that learners are not overwhelmed by the demands of the learning process, but at the same time are engaged in higher order thinking processes. Guidance aids learners in dealing with the demands of a learning process. The authors examined the effects of different levels of guidance provided by an information source. To this end, the effects of a preconstructed externalization are compared to a self-constructed externalization. Thirty-eight students participated in the study. The results revealed no significant differences between the groups with respect to posttest retention. However, performance in application tasks was promoted by the condition associated with a lower level of guidance. This suggests that having learners self-construct an externalization might be a suitable means to elicit learners' higher order thinking processes in technology-enhanced informal learning.