Teaching and Learning
Powerful Ideas

LOGO, PARC-Smalltalk, HyperCard, and starLOGO each inspired Squeak Etoys which was created by researchers at Viewpoints Research as a protoype and vehicle for teaching and learning powerful ideas.

Now supported and continually developed by a worldwide open source community, Squeak Etoys is a media-rich authoring environment with a simple but powerfully scripted object model that allows its users to create many kinds of objects and simulations. It includes 2-D and 3-D graphics, text, presentation tools, videos, sound, and MIDI. It includes the ability to share desktops with other Etoy users in real-time, so many forms of immersive mentoring and play can be done over the Internet. It is multilingual and has been used successfully in the USA, Europe, South America, Japan, Korea, India, Nepal, and elsewhere.

Here is a typical 5th grade (11-12 year-old) mathematics and science project sequence to provide an example of what we mean by a "powerful idea".

Squeak Gravity Illustrations
Examples of Etoys experiments
with acceleration and gravity

The learner would:
  • Draw objects (such as cars)
  • Write scripts to move them, have them follow edges, etc.
  • Think about speed and acceleration by leaving trails
  • Observe moving objects in the real world: dropping weights, fruits, balls, etc.
  • Use a video camera to acquire detailed records
  • Look at every 5th frame and measure the speeds
  • Compare the difference in speed between each frame
  • See that the differences (the acceleration) is constant
  • Write a script to move a simulated ball with constant accelerated motion
  • Find the constant that will match up the simulation with the real-world

This subject has been extensively studied with college students in the United States. Seventy percent (including science majors) fail to understand this Galilean model of gravity near the surface of the Earth. The Etoy projects developed use a different and simpler kind of incremental mathematics that allows very young children to understand some of the key ideas in calculus. We have found that more than ninety percent of 5th graders after completing these projects, not only understand "Galilean gravity" but are able to derive the mathematical "formulas" (actually 2nd order differential equations) using this alternative mathematics, and can author a simulation that coincides with the experimental data.

Kedama Screen
The Kedama particle
system in Etoys

Squeak Etoys also has a particle system that is scripted using the same conventions used for the larger media objects. This allows children to think through complex parts of a project, such as an ant or salmon following a scent gradient, with a few ants or fish, and then to use what has been discovered with a population of thousands of particle animals.

Finally, Squeak Etoys is a media system and web plugin that includes players and models of many kinds of media. These allow a wide range of presentations of the ideas to be made, from slides to "active essays" and immersive sessions that involve the "readers" as "co-creators".

In addition, as a developer for the $100 laptop (One Laptop per Child Initiative) the teaching and learning of powerful ideas continues to be a critical part of our mission.