The objectives of this research included to study the effects of democratic parenting and teaching activities on global citizenship according to logical reasoning in making decisions on political attitudes among 2,286 students from 80 classrooms. The research instruments included 1) a set of rating-scale questionnaires for students with 92 items, having the reliability as 0.968 and 2) a set of rating-scale questionnaires for teachers with 23 items, having the reliability as 0.893. The results of the multilevel structural equation model analysis revealed that the factor of political attitudes was the most important in describing each student's global citizenship with the explanation of the variance with democratic parenting and the analysis of applying the reasons in students' decisions was as 68.50%. Teaching activities affected positively on global citizenship both directly and indirectly through statistically significant factors with and together explained the variance of the global citizenship of each student by 84.00%. These findings highlight the importance of developing and fostering political attitudes that affect students' global citizenship through parenting and teaching activities covering the development of relevant factors as discussed in the Discussion and Implementation Part.