The term “learning technologies” usually refers to the activities that one or a few learners perform on a digital device. How do technologies take into account the fact that a classroom has many more learners? Classroom analytics provide teachers with real-time support for class management: monitoring the engagement of learners in a class; deciding when and how to intervene in their learning activities; reusing the output from one activity in another one; forming student groups; integrating the learner’s production in a lecture; deciding when to shift to another activity; or helping teachers to regulate their own behaviour. This chapter describes the classroom itself as a digital system. It speculates on how this vision can come true, and what can already be learned from it, namely the critical role of teachers in the success of digital education.