Introduced in 1992 in the educational research literature in two seminal articles by Ann Brown and Allan Collins, a design experiment (DE) is a method [Page 220]of inquiry that embodies what is today commonly called design-based research. A major characteristic is that a DE involves the development and application of an instructional intervention in a genuine educational setting. Complaints about the disconnect in education between research and theory, on the one hand, and educational practices, on the other, are still the order of the day. In view of bridging this gap, DEs have a twofold goal: advancing theory building about learning from instruction while at the same time contributing to the fundamental innovation and improvement of classroom practices. After a more detailed description of the ...