Due to their highly extended visualizing capabilities, numerical methods are very apt at demonstrating acoustic effects and phenomena. Finite-element methods (FEM) are mainly used to describe the sound fields in closed spaces, and boundary element methods (BEM) are well suited to predict radiation from vibrating bodies. Coupled systems can also be analyzed by some hybrid approaches. The paper shows applications of these tools in undergraduate and postgraduate courses of technical acoustics. Starting from the well-known concentrated parameter approach, a more realistic description of basic acoustic elements and systems consisting of acoustic masses, acoustic compliances, Helmholtz resonators, waveguides, etc. can be presented. Based on these examples, the dynamic behavior of acoustic systems such as the existence of standing waves, eigenmodes, and resonance effects can be visualized and understood. Radiation problems can be solved for elementary acoustic sources, demonstrating the basic rules of fluid–structure interaction phenomena. The most advantageous feature of numerical—FEM/BEM—calculation and visualization techniques is its capabilty to handle a large amount of data. Problems can be approached in three dimensions, both in time and frequency domain. Apart from the application areas, the lecture addresses the necessary hardware and software tools to prepare these sorts of demonstration, too.