UV-vis absorption spectroscopy is one of the most accessible spectroscopic techniques at the high school educational level, and it is usually introduced in analytical chemistry courses due to its high versatility and to the wide range of applications in many fields of chemistry. Within this framework, we have developed an easy-to-use" simulation tool" to identify and quantify the main pigments in a relatively complex food matrix, such as olive oil and seeds' oils. This digital software, freely available, can be used by high school students and first-year undergraduate students to analyze the UV-vis absorption spectrum of olive oils recorded in the bulk without any chemical treatment. In this paper, we are reporting the basic principles of the spectroscopic method and the way to use the "simulation tool" with several examples and explanations that are useful for students and teachers. In the second part of the paper, several examples of activities about the chemistry of olive oil, realized with the fifth classes' students of a high school technical institute (K-12 level) and undergraduate students of an introductory course in spectroscopy in the second year of the Chemistry Degree Course, are reported. These activities were performed partially face-to-face and partially in distance learning mode during the COVID-19 pandemic. The main learning outcomes, methodological issues, and students' feedback resulting from these experiences are reported and commented on, showing the potential of the simulation tool for educational purposes.