A unified approach to science teaching based upon a certain class of quantities which play fundamental roles in classical and modern physics is introduced. These quantities share the property of being substance‐like, that is, each can be pictured to be contained in bodies and to flow from one body to another like a kind of ‘‘stuff.’’ Such quantities include, for example, energy (=mass), momentum, angular momentum, electric charge, particle number (=amount of substance), and entropy. When emphasizing substance‐like quantities, the breakup of physics into sub‐branches is nothing more than a classification of natural processes according to the substance‐like quantity playing the dominant role in each case. The method of presentation, however, remains the same from one sub‐branch to another: different natural processes can be simply visualized and quantitatively described according to the same formal rules in terms of the increasing, decreasing, and flowing of the respective substance‐like quantities in each case. Thus knowledge of a single branch of physics already provides an analogy for the ways and means by which processes are described in other branches (including chemistry and biology) as well. These claims are illustrated with the help of a few simple examples.