Although active learning methodologies have been implemented in geoscience classes successfully, no direct comparison between these different instructional techniques exists to date. For that reason, the purpose of this study was to compare the effectiveness in student learning of two active learning methods: peer instruction and lecture tutorials. In particular, this study focuses on a first implementation of these active learning teaching methods in small- to medium -size introductory physical geology classes. Evaluation of their effectiveness was measured through the Geoscience Concept Inventory, which was administered at the beginning (pre-test) and at the end (post-test) of each course. In addition, students were asked to evaluate the contribution of these techniques to their own learning using a Likert like survey. A comparison of pre- and post-test results indicates that both methods provided statistically significant cognitive knowledge and understanding gains. A comparison of the post-test results for both methods reveals no statistical distinction, indicating a similar level of effectiveness for both peer instruction and lecture tutorials. Similarly, the vast majority of students indicated that these teaching techniques were instrumental in helping them learn different geologic concepts. The combined results of this study are consistent with others studies showing an improvement in cognitive knowledge and understanding gains whenever active learning instructional techniques are first implemented in science classes. A detailed analysis of the obtained data revealed that most of the gains were made by students having little prior knowledge of geology relative to those having some prior knowledge of geologic concepts. Given the relatively easy use of these techniques, their proven effectiveness, and the recognition by students of their effectiveness, it is then recommended that a wider implementation of these techniques should be used in introductory geology classes.