This study provides detailed descriptions, analyses, and interpretations of student interactions and participation that occurred in computer-mediated interactive writing activities in two different college classroom network situations. A freshman composition class focused on the teaching of writing through assigned exercises and incorporated electronic discussions into every other class. A plant science laboratory class used computer-based discussions to amplify what students had learned in interactive computer-based tutorials, simulations, and "traditional" hands-on activities with plant specimens. Both courses used a software program called Daedalus to manage the computer-mediated communication (CMC) activities. Daedalus contains a word processor and various support tools, an electronic mail program, and an interchange program that allows real-time "conversation." Observations and analysis of student computer use show that CMC activities can result in increased and more equal student participation in classroom activities. Students in both classes thought that the network use improved their understanding and problem-solving strategies. (Contains six references.) (SLD)