Sensor enabled smartphones have become a common platform for researchers due to their availability and ability to collect and process large quantities of data. In this work, a solution is proposed to support the student’s assessment process in physical education classes, through the use of accelerometry data collected from smartphones. This solution aims to deliver accurate and readily available information regarding student’s activity using common technologies in order to develop a low-cost approach. To develop this solution, accelerometry data was collected from several students while performing a list of activities, using a smartphone and a developed mobile app. The collected accelerometry data is used for activity information extraction such as energy expenditure and activity recognition. This information is displayed in a developed web application along with analytic charts and student information. The student accelerometry data is summarized and made available as a means to aid and complement the teacher’s assessment process and grading system. By engaging the students in the new class assessment system, the authors also hope to promote the practice of healthy exercise habits, by providing the students with visual information about their activity and allowing them to compare statistics between each other and, perhaps more importantly, evaluate their own evolution.