This experiment investigated the impact of critical thinking dispositions and instructions on economics students' performance on reasoning skills. Participants (N=183) were exposed to one of four conditions: critical thinking instruction, critical thinking instruction with self-explanation prompts during subsequent practice, critical thinking instruction with activation prompts during subsequent practice, or no critical thinking instruction or prompts (control). In all conditions, practice was a within-subjects factor, some task categories present in the test were practiced on a business case, others were not. Participants in the instruction conditions significantly outperformed participants in the control condition on the immediate and delayed post-test, but only on the practiced task categories – with the exception of the self-explanations condition, which also showed a better performance than the control condition on not-practiced categories, though only on the immediate post-test. Dispositions (i.e., Actively Open-minded Thinking and Need for Cognition) predicted reasoning skills at pre-test but did not interact with instructions on post-tests performances.