Subjective well-being is a crucial topic within Positive Psychology; it has been the subject of extensive research, especially in adults, who seek to understand what makes life more satisfying and pleasurable. However, there is still a scarcity of studies aimed at understanding and explaining how satisfied people are with their lives and the positive–negative affects during childhood. This chapter aims to give an overview of the concept of well-being, and its distinction between the eudaimonic and hedonic perspectives, where the approaches to well-being are from the notion of the cognitive (life satisfaction) and affective (positive affect, negative affect) components. Due to its complexity, a model is proposed with variables such as daily stressors, depression, self-efficacy, and resilience, which explain subjective well-being in a sample of schoolboys and girls from Toluca, Mexico. Measurement scales were applied to each variable of interest, the results showed high levels of satisfaction, there were no differences between boys and girls, and the correlation and prediction analyses allowed proposing the implementation of the model through structural equations. The hypothesized model is confirmed since the fit indices are acceptable. It is necessary to continue studying well-being in these age groups and analyzing its components and domains to explain which specific areas of satisfaction could warn of the possible directions of the subjective well-being configuration within Mexican samples.