The traditional teaching of physics in separate domains leads to a fragmented knowledge structure that has an adverse effect on the comprehension and recall of the central ideas. We describe a new program: MAOF ("overview" in Hebrew), which relates large parts of mechanics and electromagnetism to each other via the key concepts of field and potential, and at the same time treats students' conceptual difficulties. The MAOF program can accompany any conventional course in mechanics and electromagnetism as part of the review process. The instructional model integrates problem solving, conceptual understanding, and the construction of a knowledge structure. It consists of five stages: solve, reflect, conceptualize, apply, and link. In order to construct the relationships within a domain, students solve simple and familiar problems, reflect on their solution methods, identify the underlying principles, and represent them in visual form, forming concept maps. Additional activities deal with conceptual difficulties and application of the information represented in the concept map. The maps are constructed at different levels of detail and are applied in further problem solving. Students who studied with MAOF significantly improved their understanding of central ideas associated with fields and potentials. They improved their understanding of the relationship between general concepts and their examples, and could better solve familiar and unfamiliar problems using these concepts.