After ten years of deployment of the Sugar Learning Platform, we reflect on the specific tools and affordances deployed to engage learners in computational thinking with the overarching goal of fluency. These tools include multiple media-rich programming environments and also mechanism for debugging, collaboration, expression, and reflection. We motivate our selection of tools by reviewing the pioneering work of Seymour Papert, Marvin Minsky, and Cynthia Solomon, who first brought multimedia computing to elementary schools in the late 1960s with the goal of engaging children in the mastery of many of the heuristics and algorithms we associate with computational thinking. Multiple examples of how these tools have been used by teachers and students are discussed. We further describe the role that Free/Libre Software plays in providing scaffolding for deep and personal expression through programming and for surfacing personal responsibility, a sense of community, and unbounded expectations of Sugar users turned Sugar developers. Keywords: Constructionism, Programming, Logo, Free/Libre Software, Computational Thinking Resumen Diez años después del lanzamiento de Sugar Learning Platform, reflexionamos sobre las herramientas específicas y las affordances educativas promovidas por esta plataforma para 1 Nota del editor: El término "affordance educativa" ha adquirido un significado que se relaciona con "la respuesta a la búsqueda de expresar las propiedades de un entorno que, al interactuar con un usuario, mejora el potencial de aprendizaje". En palabras de Kirschner (2002, p.14) :"Educational affordances are those characteristics of an artifact (e.g. how a chosen educational paradigm is implemented) that determine if and how a particular learning behavior could possibly be enacted within a given context (e.g., project team, distributed learning community). Educational affordances can be defined [...] as the relationships between the properties of an educational intervention and the characteristics of the learner (for CSCL: learner and learning group) that enable particular kinds of learning by him/her (for CSCL: members of the group too)." "Affordances educativas son las características de un artefacto (por ejemplo, cómo se implementa un paradigma educativo determinado) que determinan si una modalidad particular de aprendizaje podría ser asumida en un contexto determinado (por ejemplo, trabajar un proyecto en equipo, establecer una comunidad de aprendizaje distribuido) y cómo se produce. Una affordance educativa se puede definir [...] como las relaciones entre las propiedades de una intervención educativa y las características de los alumnos que permiten que se produzcan determinados tipos de aprendizaje en ellos. "