Online Social Networks (OSN) are the new tools that students are using to interact, communicate and collaborate for school work. The impact on school activities, as well as the communication mechanisms among students, have just started to be studied. This research focuses on this issue, trying to answer the question: How do college students use OSN to improve communication and exchange knowledge? For this purpose we used the application of two online surveys applied to students of business administration (BBA - Bachelor in Business Administration) and informatics management (BIM – Bachelor in Informatics Management) students in 2010 and 2012 in Mexico. Our findings reveal that business administration students are the ones that use these kinds of platforms more frequently for sharing information and communicating with their peers. The comparison of these two surveys shows how the behavior and activities among students have changed.