PLATA: Design of an Online Platform for Chemistry Undergraduate Fully Automated Assignments

In the Digital Era, the development of new educational instruments is crucial for supporting students in their academic journey. While there is a significant correlation between homework and learning, the effectiveness of assignments is often constrained by the large number of students and the extensive grading required by teachers. In this context, open educational resources (OER), particularly those built on the free and open-source Moodle platform, have shown increased learning among students, becoming valuable instruments for educators. Automated chemistry assignments are challenging, in contrast to physics or mathematics. This is due to the necessity of accounting for the vast yet finite universe of existing molecules, compounds, and reactions along with the inherent constraints imposed within the field. In this article we present PLATA (Programa en Linea de Apoyo a las Tareas Academicas), a Moodle based OER for automated chemistry homework implemented at Facultad de Quimica at UNAM. PLATA is an online platform with more than 132 million open answer exercises (not multiple choice) automatically graded with specific feedback for each exercise attempt. The design and characteristics of the program, some examples showing its versatility, and the outstanding students' outcomes of the OER are presented. PLATA has been used by more than 15,500 students over the past 4 years. The results displayed correspond to the 2022 academic year, with more than 3,200 students, from which 500 undergraduates answered an exit survey, and we monitored the outcomes of 400 students. As a result, we can state that PLATA is a versatile, useful, and robust program for chemistry assignments with a positive impact on students' learning.