As one of the most complicated and also among the touchiest of educational domains, sex education has always been subject to many obstacles due to existing misconceptions and areas of lack of clarity, which has led to the rise of social problems and abnormalities in behavior among youth. The present research has thus endeavored to determine the ten elements involved in the curriculum for sex education throughout primary to secondary education levels. To this aim, the studies carried out in Iran from 2001 to 2020 and abroad from 1990 to 2020 regarding sex education, sexual well-being and the curriculum elements involved in sexual education were examined, which led to 66 studies being selected for the sample, and Roberts' six-step synthesis research model was used to achieve the optimum combination of results. Checklists were used for data collection, and reliability was ensured by using Cohen's kappa coefficient. NVivo 8 was used for data analysis. The findings indicated that the objectives of sex education consist of providing the knowledge, skills and attitudes needed to enable the individual to conduct healthy sexual affairs in personal as well as social affairs. The content depends on the objectives for each course, and active approaches of teaching prove more appropriate. The teacher has the role of a counselor, and a variety of sources can be used. There is flexibility in time and place, activities need to be conducted in small groups, and qualitative methods of evaluation are of significance.