PurposeThe purpose of this study is to help teachers resolve the difficulties in assessing the students' characters through the development of valid, reliable, goodness-of-fit statistic instrument of emotional and social intelligence assessment for elementary school students.Design/methodology/approachThis study used a research and development model from Plomp with five phases, such as investigation, design, realization, testing and implementation. The research subjects were 345 students of class IV amongst 20 elementary schools in Yogyakarta. Data collection used questionnaires, documentation, interviews, Forum Group Discussion and an observation. Data analysis used descriptive analysis, Aiken's V, exploratory factor analysis and confirmatory factor analysis formulae.FindingsThe research study helps solve the difficulties of teachers in assessing emotional and social intelligence, which have previously been in only one area of psychomotor. The design of emotional and social intelligence assessment instruments is made from three domains of character, namely, cognitive, affective and psychomotor. The form of the instrument is non-test in three variations. The construct of social and emotional intelligence assessment for a character reinforcement has met the validity, reliability and goodness-of-fit statistic.Research limitations/implicationsThis study explains that the Emotional and Social Intelligence (ESI) model is applied for measuring cognitive, affective and psychomotor in children. This study proves that the ESI model is a comprehensive assessment model for evaluating the children's soft skills, includes (1) personal abilities: the ability to make rational decisions, the ability to design the future and (2) social skills: the ability to work together and the ability to understand other people.Practical implicationsTeachers can measure and determine the condition of children's soft skills by operating the ESI model. Based on the knowledge of the correct soft skill conditions, the teacher can adjust the teaching materials and teaching methods that would improve the child's soft skills regarding to their respective conditions. Mastering these soft skills will affect the children's capability in facing the challenge in the upcoming society's life.Originality/valueThe novelty of this study is the design model of the emotional and social intelligence assessment instrument developed comprehensively and practically as it is created from three domains of character and three forms of non-test questions, so that the assessment is not mechanical, and easily practiced by users.