Mitchel Resnick John Maloney Andrés Monroy-Hernández Natalie Rusk Evelyn Eastmond Karen Brennan Amon Millner Eric Rosenbaum Jay S. Silver Brian Silverman Yasmin B. Kafai Scratch: programming for all. 60-67 2009 52 Commun. ACM 11 http://doi.acm.org/10.1145/1592761.1592779 db/journals/cacm/cacm52.html#ResnickMMREBMRSSK09