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Molecular models derived from results of quantum-chemical calculations present an important category of didactic instruments in chemistry education. These models can be used especially as tools for supporting the students’ understanding by visual learning, which can adequately address complexity of many chemical topics, incorporate appropriate didactic principles, as well as utilize the benefits brought up by the actual information technology. The proposed molecular models are non-trivial examples of didactic application of computational chemistry techniques in illustration of electron interactions in amidic group, namely the interaction of the free electron pair on the nitrogen atom with the carbonyl group and also the interaction of atoms in the amide group with other surrounding atoms in the molecule. By these molecular models it is possible to explain acid-base properties of amides applying knowledge of electron density distribution in the molecules and the resulting electrostatic potential. Presentation of the structure and properties of the amides within education is important also for the reason that amidic functions are involved in many important natural substances (e.g. proteins, peptides, nucleic acids or alkaloids), synthetic macromolecular substances (e.g. Silon) or pharmaceutical preparations (e.g. paracetamol). This paper investigated the effect of using different types of models while teaching organic chemistry on student understanding of new concepts and the spatial structure of new molecules, as well as preference of a particular model type and illustrates the possibilities of computer-assisted molecular modelling in supporting chemistry teaching and learning. Keywords: Molecular models, Acidity, Amides, Basicity, Electrostatic potential