High school chemistry courses show several challenges. It is difficult to explain highly abstract and complex topics within the limited time available, and students may struggle to grasp concepts that can appear like dogma. Topics such as atomic structure, quantum mechanics and chemical bonding require a balance of scientific accuracy and clear, accessible explanations. In this work, we focus on how some key ideas can be taught more effectively, spanning from the Bohr atomic model to the chemical bonding and the concept of electronegativity. The Bohr model represents an important step for students, as it introduces the concept of quantization in a relatively simple and intuitive way, through discrete atomic radius and energy levels. From here, the transition to the quantum model of Schrödinger helps students to understand a new way of describing objects at the atomic scale, such as electrons, no longer as particles in orbits but as entities described by wavefunctions and quantum numbers. Next, with a sufficiently straightforward understanding of the quantum nature of the atom, we will examine the reasons why chemical bonds form, referring to the works of Heitler, London and Pauling. Finally, we will discuss how chemists simplify physical complexity by defining simple descriptors such as electronegativity, focusing on the works of Pauling and Mulliken. Overall, the article emphasises the importance of effective teaching strategies in chemistry, encouraging teachers to use models as helpful tools for guiding understanding rather than presenting them as absolute and rigid truths.