Social network sites such as Facebook are often conceived of as purely social spaces; however, as these sites have evolved, so have the ways in which students are using them. In this study, we examine how undergraduate students use the social network site Facebook to engage in classroom-related collaborative activities (e.g., arranging study groups, learning about course processes) to show how Facebook may be used as an informal tool that students use to organize their classroom experiences, and explore the factors that predict type of use. Data from two surveys (N = 302, N = 214) are used to analyze how Facebook use, social and psychological factors, self-efficacy, and types of instructor-student communication on Facebook are related to positive and negative collaboration among students. We found that predictors of Facebook use for class organizing behaviors include self-efficacy and perceived motivation to communicate with others using the site. When placed in the context of social and psychological factors, Facebook intensity did not predict either positive or negative collaboration, suggesting that how students used the site, rather than how often they used the tool or how important they felt it was, affected their propensity to collaborate.