Apropos of conceptualisation, EI was conceptually defined by Salovey and Mayer as social intelligence encompassing the abilities to monitor and understand the emotions of the self and others [3]. Therefore, the training of socio-emotional skills for students is becoming necessary, and most teachers consider these skills to be essential [7,12,15,16]. According to Ibarrola [11], the education system is lame, as long as it does not incorporate EE, stating that many academic performance problems have their origin in emotional issues and not in a lack of skill. Additionally, it is increasingly evident that general success and well-being in adulthood may result from early childhood learning by using these social and emotional skills to productively cope with life changes, as they reduce the risk of suffering as a result of mental health problems and improve psychological well-being [17]. Within the clinical psychology framework, experiences showed that the key to determining and predicting success was not only a matter of cognitive intelligence, since some people with supposedly high intelligence were not successful in life, while others with less intelligence obtained much more outstanding achievements.

Schools are the ideal place for the promotion of EI [1,17]. In this sense, Gardner’s Theory of Multiple Intelligences (1983) has been considered as the most influential work in the field of Education. According to this author, intelligence changes and develops, based on the individual’s experiences throughout his or her life, resulting from the interaction between biological and environmental factors. For Gardner [18], humans are better defined by saying that they have a series of relatively independent bits of intelligence than by establishing a single intelligence defined by an IQ. More specifically, he affirms that there are many ways to be intelligent. Despite the criticism it received, it is inevitable that Gardner’s theory highlighted inter-individual variability in the classroom and that there must be different teaching methods adapted to that form of education. Another advantage of Gardner’s view is that it has many direct educational practice applications, advocating a teaching–learning process that develops learners’ intelligence. Thus, Gardner’s Theory of Multiple Intelligences is the basis for creating and applying novel, motivating, integrative, and creative strategies, so that students, in their leading role, build broad knowledge schemes. Compared to others, this perspective goes beyond everyday knowledge limits, bringing them closer to understanding and creative potential by developing or activating other bits of intelligence [19].

2. Emotional Intelligence in Education Settings

Socio-emotional skills deficiencies affect students inside and outside the school context [15]. There are four fundamental areas in which a lack of EI causes or facilitates behaviour problems among students: interpersonal relationships, psychological well-being, academic performance, and disruptive behaviours. According to the review carried out by Zeidner et al. [19], some beneficial effects of emotional skills work stand out, such as the regulation of emotions and a positive attitude, and the reduction in counterproductive or distorting behaviours, such as stress or anxiety. Other studies reveal the benefits of having high EI levels. In this regard, an improvement to psychological well-being influences the mental health of school children, allowing them to acquire an emotional balance to enhance their academic performance [15,17].

Being educated at school, in terms of emotions, should be considered a curricular priority. EE programmes can reduce maladaptive behaviours and favour general well-being at intrapersonal and interpersonal levels; at an intrapersonal level, providing strategies for emotional and social regulation, and, at an interpersonal level, increasing strategies to manage the emotions of others [15]. Thus, the aspects, such as self-esteem, can significantly increase the well-being of students, while, at the same time, allowing them to improve the performance and climate in the classrooms. Receiving an education in emotional skills helps students to become aware of their emotions and those of others. Additionally, it enables them to understand and regulate themselves, has beneficial effects on the physical and psychological health of adolescents on multiple levels, and positively impacts their academic performance [8]. Above all, the development of socio-emotional competencies in adolescence, which has repercussions in adult life, is a nonspecific prevention formula for drug use, stress, anxiety, and violence, thus reducing vulnerability and increasing self-esteem and skills that allow individuals to adopt a positive attitude towards life [16,20].