Millions of users use online, open-ended blocks programming environments like App Inventor to learn how to program and to build personally meaningful programs and apps. As part of understanding the computational thinking concepts being learned by these users, we want to distinguish original projects that they create from unoriginal ones that arise from learning activities like tutorials and exercises. Given all the projects of students taking an App Inventor course, we describe how to automatically classify them as original vs. unoriginal using a hierarchical clustering technique. Although our current analysis focuses only on a small group of users (16 students taking a course in our institution) and their 902 projects, our findings establish a foundation for extending this analysis to larger groups of users.