This article describes the technology of teaching the theme “Arithmetic circuits: design, simulation and debugging” of basic digital electronics course to first/second-year students based on the DL.GSU.BY website. The main advantages of the technology include training adapted to the student, many years of experience in practical application, and effectiveness. The following issues are consistently considered in the article: the theoretical foundations of the topic; a library of standard components; a system of step-by-step learning to design arithmetic circuits, and a technology for simulation and debugging.