Physiology instructors often are faced with the challenge of providing informative and educationally stimulating laboratories while trying to design them in such a way that encourages students to be actively involved in their own learning. With many laboratory experiments designed with simplicity and efficiency as the primary focus, it is sometimes difficult to design in-class experiments that are able to meet all of the above criteria. This article describes an approach being used at Michigan State University to help make the undergraduate laboratory exercise more "minds on," taking elements from each of the four instruction techniques for teaching physiology labs (expository, inquiry, discovery, and problem based.) In this new model, students use information provided to them in a prelaboratory lecture about the topic of study and then must formulate a hypothesis, answering guided prompts from the lecture to form a hypothesis about the outcome of the upcoming experiments and then turn in this hypothesis to the instructor as well as write it in their weekly homework. By turning in a copy of the hypothesis before they perform the experiment, this ensures that students do not alter their hypothesis after seeing the results of the pooled class data. Not being able to alter the hypothesis is a critical component to the success of this laboratory model. Not only does this prevent students from altering their hypothesis to match the "correct" or "expected" results, but it also reinforces the idea that wrong ideas and expectations are not "incorrect" but rather offer opportunities for better understanding. In semesters that did not use this method of turning in the hypothesis, problems arose with students often making incorrect predictions about the laboratory and feeling the need to change their hypothesis to match their observed results in their weekly homework after the experiment had been completed. Adding a hypothesis-generating exercise to each laboratory experiment is a mentally stimulating exercise that forces students to become involved in the laboratory they are performing. This participation forces engagement and critical thinking from the student and allows for immediate confirmation or rejection of their proposed hypothesis upon completion of the laboratory when the pooled class data is displayed. The addition of a hypothesis generation activity increases student investment in laboratory experiments and helped lead to a commitment to quality for in class data partly due to this prediction and immediate feedback. Through these elements and changes to the laboratory environment, curiosity and enthusiasm are fostered and a better learning environment and a more productive classroom are created.