The purpose of this study was to identify international trends in K-12 computer science curricula in countries that have introduced computer science education. Content analysis method was used to analyse the country-wide curricula of 10 countries which have introduced computer science education at the primary level. The K-12 Computer Science Framework was used as a theoretical frame to analyse the curricula. The results show that most countries begin their curricula with sub concepts of "algorithms," "program development," and under "impact of computing," along with the practice of creating computational artifacts; then, countries expand upon computer science concepts and practices as learners progressed through the higher grades. Further, countries tend to introduce computer science concepts and practices in stages; once concepts and practices are introduced, they continue across multiple grades. Three approaches to implementing computer science education into the country-wide curriculum were found: introducing computer science (a) as an independent subject, (b) within multiple subjects, and/or (c) as a part of transversal competencies or an independent computer science curriculum with a cross-curricular approach. These study findings can contribute to a worldwide effort to introduce computer science education at the primary level.