Dedication

To my father, Eddie (r.i.p), who inspired me to explore the use of computers and passed on his dream of going to MIT.
To my mother, Chichi, who always emphasized the value and joy of reading.
To my wife, Liliana (a.k.a Lilo), who gives meaning to the things I do (always) and feels proud of me (almost always).
To Domingo, Teresa, and Francisco, who are our greatest challenge and our happiest adventure.
To my uncle, Jorge A. Rizzi (h), who gave me my first job at SADOI, twice.
To Jorge A. Rey Valzacchi, a pioneer in integrating technology into education in Argentina.
To Rosa Kaufman, a pioneer of LOGO in education in Argentina.
To my friends, who never understood what my work is about, but love me nonetheless.