The growth theory has, through the so-called ‘endogenous’ or new growth theory, taken on decisive impulses. This contribution delivers an overview of the various extensions without going into detail about the mathematical observations and the main focus on supply-side orientated approaches. The main goals of the growth theory are to understand the exponential climb of the population’s income or also the per‑capita income and to draw conclusions for policy makers. The paper uses stock-flow-graphs to visualize the major loops. Because changes tend to be incremental I adopt standard textbook models first. All models are used in economic teaching with additional simulation and extensions. Later on students learn to modify those models.