The annual Bebras challenge aims to grow students' interest in computer science via engaging problem solving tasks whereas ViLLE is a widely used digital learning environment with a built-in assessment tool and analytics for large number of students. The BeLLE collaboration connects the two by adapting ViLLE's assessment tool in the Bebras challenge. The goal is to analyze the interplay of computer science education and students' computational thinking development in the participating countries. BeLLE welcomes new interested countries to join the collaboration.