In a sample of N = 105 fifth graders from Vietnam and Germany, cognitive abilities (CogAT-Nonverbal, i.e. fluid figural, CogAT-Quantitative, i.e. crystallized mathematics), family attributes, parenting styles, leisure time activities, and attributes of school and instruction were compared. In spite of large cultural and economic differences, the general cognitive ability levels were similar (M Vnm = 99.43 vs. M Deu = 99.13 IQ points in current UK norms). This result is in contradiction to usual outcomes in developing countries. However, regarding family, parenting, school and instruction, differences were observed: German families had more books. German parents were less frequently married and German families less frequently consisted of both mother and father. Vietnamese parents had more children. Vietnamese parents showed higher levels of authoritarian and neglecting parenting. German children read more books. The Vietnamese did not attend kindergarten, had larger classes, more homework, and more private tuition. In a path analysis, parental educational level, number of books, burgher family, low birth order rank, amount of teaching, parental income, Confucian educational orientation and Vietnamese background all revealed a positive impact on children's intelligence.