In recent years, there has been a growing interest in making education widely accessible using Internet technologies. Whether it is Massive Open Online Courses (MOOCs) or simply college courses offered to a large student population using an online platform, both education-focused companies and universities, often in collaboration with one another, have been investing massively in online education. The fact that hundreds, and more often thousands, of students take these online courses raises scalability challenges in assessing student assignments. In this paper, in particular, we present a technique (GUITestMigrator) that addresses the challenge of assessing mobile app coding assignments. Given a set of apps that implement the same specification, but can have completely different user interfaces, instructors normally have to manually run and check each app to make sure it behaves correctly and according to the specification. GUITestMigrator, conversely, allows for developing tests for one of these apps and automatically migrating these tests to the other apps, thus dramatically reducing the burden on the instructor. We implemented GUITestMigrator for Android apps and evaluated it on three sets of apps developed over three different semesters by students of an online graduate-level software engineering course. Our initial results show that our approach is promising and motivates further research in this direction. The paper also discusses possible applications of this approach for test evolution and test migration for real-world apps.