SUMMARY
Teaching of general and special disciplines at physical faculty is impossible without a demonstration experiment, but not always the laboratory material resources correspond to the up-to-date level of a hardware. The usage of the out-of-date equipment reduces interest to a subject because students do not see application of the gained skills of operation with devices in their further industrial activity. As an exit from such problem situation the usage of interactive educational models can serve. In this connection the authors develop interactive computer models in the form of the separate program modules, intended for demonstration of thermal processes in systems with changeable number of particles at studying of the first and second principles of thermodynamics in «Molecular physics».