This study investigates the effectiveness of scaffolded game development activities in enhancing computational thinking (CT) skills among young learners using a graphical programming environment. While prior research highlights the value of block-based programming in CT education, few studies explore how structured scaffolding supports learners in completing full game projects. Grounded in Vygotsky’s Zone of Proximal Development and Wing’s CT framework, this study involved 310 participants aged 10 to 15, including their teachers, in a tiered sequence of programming tasks using mBlock programming platform. Learners progressed from basic to more complex programming constructs, namely, loops, conditionals, variables, and debugging, which are included in the development of a complete Pac-Man or Snake game. Quantitative results demonstrated significant improvements in CT skills across all age groups. Qualitative data revealed increased learner engagement, reduced programming anxiety, and enhanced interest in computational problem-solving. The findings suggest that scaffolded game development is a promising strategy for early CT instruction, offering both cognitive and affective benefits. This work contributes to current literature by demonstrating how structured support and creative programming tasks can jointly promote CT proficiency and learner motivation in foundational computing education.