Instant messaging with Internet-based software is a ubiquitous form of communication in industrialized nations. In fact, many educators are observing that students engage with instant messaging while simultaneously engaged in academic activity. Though this type of multitasking is pervasive, educational researchers have not examined how the practice of instant messaging impacts learning outcomes. This dissertation describes the background, empirical and theoretical foundations, methods and results of a study examining the impact of instant messaging activity on learning, where instant messaging and learning are simultaneous activities. The question posed is grounded in the related areas of instant messaging practices, the Generation M profile, Cognitive Load Theory, and integration of instant messaging in K-16 classrooms. This work presents empirical evidence pointing out the necessity of conducting empirical study regarding how instant messaging activity might impact learning. Quantitative methods used to conduct the study are presented including data collection instruments. The results of the study are discussed in broad terms related to Generation M and Cognitive Load Theory. Methodological limitations related to practice opportunities for the research sample as well as the performance measure used are detailed. In addition, implications of the results in relationship to those teaching members of Generation M in K-16 classrooms as well as those designing instruction for this population are discussed. The discussion concludes with recommendations for further research in this area.