One-to-one technology involves equipping each child with a computing device that provides personalized learning tools. While one-to-one learning is showing promise in classrooms, it has revealed problems, including management of the technology-enabled classroom, lack of support for collaborative and whole class working, the design of lessons that switch easily between activities, and difficulty in re-use of lesson components. In this paper we describe the SceDer system to orchestrate learning with one-to-one technologies. It provides an authoring system for teachers to design lessons, an interchange language to describe lesson sequences and resources, and a delivery system that enables the teacher to manage collaborative one-to-one learning in the classroom. The system has been tested in school classrooms and the results show that it is effective in managing a fluid movement between individual, group, and whole class learning activities.