In this paper we analyze the usage of ExaNet: an online exam and evaluation management tool. To do so, we proceeded to use this tool to evaluate the knowledge of students in several courses with (at our university and at some local high schools). We tested students in a wide variety of topics, from different Math courses to Music. The tool was developed with the aim of improving the actual strategies to implement mathematical formulas for online exams on the web. We include a preliminary statistical study of the results for some particular tests.