The high ceiling means that the tools are powerful and can create sophisticated, complete solutions.

Seymour’s approach built on what he had learned from Piaget, viewing children as active constructors, not passive recipients, of knowledge. Seymour went a step further, arguing that children construct knowledge most effectively when they are actively involved in constructing things in the world — that is, when they are makers of things. Seymour called his approach constructionism, because it brings together two types of construction: As children construct things in the world, they construct new ideas in their heads, which motivates them to construct new things in the world, and on and on, in a never-ending spiral of learning.

The term "constructionism" first coined by Seymour Papert, involves two types of construction. First, it asserts that learning is an active process, in which people actively construct knowledge from their experiences in the world. (This idea is based on the theories of Jean Piaget.) To this, constructionism adds the idea that people construct new knowledge with particular effectiveness when they are engaged in constructing personally meaningful products. They might be constructing sand castles, LEGO machines, computer programs, or virtual objects. What's important is that they are actively engaged in creating something that is meaningful to themselves and to others around them.

Constructionism [Papert, 1991] is both a theory of learning and a strategy for education. Constructionism is based on two types of "construction." First, it asserts that learning is an active process, in which people actively construct knowledge from their experiences in the world. People don't get ideas; they make them. (This idea is based on the constructivist theories of Jean Piaget.) To this, constructionism adds the idea that people construct new knowledge with particular effectiveness when they are engaged in constructing personally-meaningful products. They might be constructing sand castles, poems, LEG0 machines [Resnick, 1993], or computer programs [Harel, 1991; Kafai, 1995]. What's important is that they are actively engaged in creating something that is meaningful to themselves or to others around them.

Constructionism involves two types of construction. First, it asserts that learning is an active process, in which people actively construct knowledge from their experiences in the world. (This idea is based on the constructivist theories of Jean Plaget.) To this, constructionism adds the idea that people construct new knowledge with particular effectiveness when they are engaged in constructing products that are personally meaningful. They might be constructing sand casdes, LEGO machines, or computer programs. What's important is that they are actively engaged in creating something that is meaningful to themselves or to others around them.

The low threshold means that the interface should not be intimidating, and should give users immediate confidence that they can succeed.

MUDS are text-based virtual worlds in which participants literally construct the world in which they live, writing programs to define the behaviors of objects in the online world. MUDs began as multi-player game environments, but they have evolved into more general-purpose meeting places on the Internet, where people gather to enjoy one another's virtual company and to work together to extend the virtual world. For example, you can decide to be a purple bird and build yourself a nest, or you can become a munchkin and join others in building a replica of Oz.

Scratch is a networked, media-rich programming environment designed to enhance the development of technological fluency at after-school centers in economically-disadvantaged communities.