This chapter describes the design and development of a constructed response system. The classroom interaction system (CIS) is a retro-hybrid technology that recovers most of the benefits of traditional slates while overcoming many of their limitations. Using “neo-slates” (handheld computers), students create responses to instructor prompts and submit them wirelessly to the teacher. The teacher may then, anonymously, present enlarged versions of exemplary, alternative, or erroneous student-generated representations to the class to illuminate concepts, enhance discussions and support student learning. The teacher can also review the database of student responses to support assessment, reflection, and follow-up intervention. Continuing development plans are discussed.