Computational Thinking (CT) is increasingly recognized as a fundamental skill for all students. However, its integration into educational systems remains a challenge. In Portugal, CT is embedded within Mathematics and Information and Communication Technologies (ICT) curricula. However, many Mathematics teachers struggle to effectively teach CT concepts due to a lack of formal training. In ICT, limited instructional time—50 min classes every two weeks—hinders the development of CT skills. To address these limitations, a School Cluster implemented a pilot CT subject as a complementary component of the curriculum for students from the 3 \(^{\text {rd}}\) to the 6 \(^{\text {th}}\) grade. This paper presents the design, methodology, and implementation of this initiative, along with preliminary reflections on its effectiveness. The study discusses the challenges encountered, the viability of curricular integration, and the potential for expanding this initiative into a mandatory subject within the national curriculum.