Effective physics analogies

The abstract nature of physics concepts particularly challenges teachers and students. For instance, how do we describe forces, in particular, forces that act at a distance, like gravity, magnetism, and electric force? How can we explain refraction? A ray of light bends toward the normal as it passes from air to water because it slows down, by why does it slow down and how does this slowing down change the direction of a photon? And how do we easily explain nuclear decay and radioactivity? sophisticated quantum explanations are available to physicists, but where are the everyday explanations that school teachers can use with elementary and middle school students?