Past research has shown that the use of tangible platforms for computingeducation can enhance students’ interest, engagement and collaboration within workgroups. However, to this day, the adoption of such interfaces in classrooms has remained relatively scarce. This is possibly due to the expenses and efforts necessary to acquire, set up and maintain such platforms. In this context, the use of paper as a principal means of interaction represents an inexpensive and versatile solution, that additionally harnesses the prevalence of paper in classrooms. This work, therefore, introduces PaPL, an easily reproducible platform for paper-based programming languages. The platform was evaluated in two exploratory user studies, where it was used to program the educational robot Thymio. The first study aimed to investigate the interaction of over 100 senior year high school students with the platform under varying conditions of group size and usage constraints. In the second study, the platform was tested with 32 sixth-graders and 2 teachers to evaluate its usage in an authentic context. The results indicate that group size, as well as usage constraints, may affect students’ interaction with the platform. Moreover, the classroom study shows promising results with regard to the use of PaPL in formal education.