With the coming of quantum information and associated technologies, there is increasing need to prepare students on the fundamentals of quantum physics. Fundamental physical principles can be hidden by the mathematical formalism of quantum mechanics. Thus it is necessary to expose students to experiments that illustrate fundamentals. Quantum optics experiments based on the generation of twin photons via spontaneous parametric down-conversion have many advantages, such as being simple, reliable, and of reasonable cost. These types of experiments are ideal for the advanced laboratory in the physics curriculum. At Colgate University we offer them as a laboratory package that is associated with our upper-level undergraduate course on quantum mechanics. In this article we present our latest approaches. Among them is a new layout for the experiments to provide a more intuitive physical picture.