Historical introduction / J. Michael Spector and Lin Lin -- The sciences of learning / Pablo N. Pirnay-Dummer and Norbert M. Seel -- Finding a middle ground : wars never settle anything / Paul A. Kirschner and Kristine Lund -- Comparing the goals and methodologies of learning scientists and educational technology researchers / Thomas C. Reeves and Eunjung Grace -- Learning sciences and instructional design : big challenges, multi-field, multidisciplinary solutions / Wellesley R. Foshay and Jeremy Roschelle -- Implications : cherishing the middle ground / Jan Elen -- Reconsidering design and evaluation / Andrew S. Gibbons and David D. Williams -- Learning science applications for research in medicine / Susanne P. Lajoie -- An asian perspective on the divide / Allan H.K. Yuen -- The collaboration imperative / Ellen B. Meier -- Synthetic environmnts for skills training and practice / Robert Hubal and Thomas Parsons -- Instructional design and learning design / Nancy Law -- Learning analytics design / Dirk Ifenthaler -- Continuing the discourse / Lin Lin and J. Michael Spector