The purpose of this work is to find out the students’ perception of the level of development of competences in the area of Social Sciences, Geography, and History. It has been developed taking into account what has been learned in the area, the level of difficulty for its acquisition, the assessment tools, and the transfer to a real situation. The development of a scale—original and unprecedented—called Evaluation of the Perception of Competences from the Social Sciences (EPECOSICO) has allowed, through a descriptive and quantitative study of validation of the instrument with an intentional sampling, to know the opinion of more than 1400 students of 4th year of secondary education (Spain). The instrument used presents good psychometric attributes, emphasizing the balanced characterization, considering that the number of students is similar (51%, 49%), the confidentiality and the validity. Finally, a KMO higher than 0.9 indicates high reliability in the consistency of the instrument used.