Students hold foundational assumptions that interact with information they are introduced to in college. By learning to identify, assess, and restructure these foundational ideas, students' ability to acquire topical knowledge improves. This article presents a format for teaching students how to evaluate their beliefs through four levels of critical thinking: (1) identifying assumptions, (2) assessing the origin and quality of assumptions, (3) seeking out alternative perspectives, and (4) weighing evidence and incorporating new information into thinking. A variety of skills are needed to accomplish each of these levels, such as identifying biases and developing intellectual humility. Self-assessments, assignments, and responses to early and late semester questionnaires suggest students see the value in learning about critical thinking and develop their ability to think critically over the course of the semester. Students become more open-minded, intellectually humble, and self-reflective, priming them to be more receptive to foundational learning.