I examined students' discourse while working in pairs at the computer in an eighth-grade mathematics class to understand how students kept track of the people and things they discussed. I found that students most often referenced themselves and objects within the environment, through references to shared knowledge and the representations on the computer screen. Through these references, students communicated themselves as agents doing mathematical work situated through the use of the programming environment. This study contributes to articulating the complexity of students' mathematical discourse when they work with peers, using technology, for doing mathematics.