NetTango: A Mash-Up of NetLogo and Tern

• In Event: When Systems Collide: Challenges and Opportunities in Learning Technology Mash-Ups

Abstract

The Technologies: NetLogo is a popular agent-based modeling environment developed by Uri Wilensky and the Center for Connected Learning and Computer-Based Modeling at Northwestern University (Wilensky, 1999). We view agent-based modeling as a form of computational thinking in which elements of a complex system are represented by computational entities whose interactions result in emergent whole-system behaviors (Wilensky & Reisman, 2006). NetLogo models describe sets of rules that govern the behaviors of individual computational agents (e.g. sheep, wolves, and grass) in a system. As a model runs, interactions between agents, all concurrently acting out their rules, can help learners understand complex, real-world phenomena.

Tern is a tangible computer programming language that was developed by Michael Horn at Tufts University. Using Tern, children can create simple computer programs by constructing chains of wooden blocks. These blocks represent physical algorithmic structures that can be executed by a robot or some other computational agent. Tern is based on simple and reliable computer vision technology, making it inexpensive and practical for use in learning settings like classrooms and museums. Tern is featured in a computer programming and robotics exhibit at the Boston Museum of Science and as part of a curriculum unit designed for early elementary school classrooms (Horn, Crouser, & Bers, 2011).

The Vision: Wilensky and Horn teamed up when Horn joined the faculty at Northwestern University. The vision of the collaboration was simple—increase the accessibility of NetLogo for a younger audience and figure out a way to scaffold student learning, not only in terms of experimenting with NetLogo models, but also in terms of building their own models from scratch. With Tern we knew we had a good track record of encouraging a diverse audience to experiment with computer programming basics (Horn, Solovey, Crouser, and Jacob, 2009; Horn, Crouser, & Bers, 2011). Likewise, with NetLogo, we knew that we had a tool that could promote deep and meaningful engagement in a variety of content areas from chemistry to evolution. The trick, however, was making these two technologies work together to create a compelling learning environment. Our mashup, called NetTango, uses a multi-touch tabletop technology as the interaction platform to bridge the physical world of Tern with the virtual world of NetLogo (Olson, Leong, Wilensky, & Horn, 2011; Olson & Horn, 2011). In other words, the tabletop allows children to interact with NetLogo models using direct touch input while at the same time creating NetLogo programs using physical blocks tagged with computer vision fiducials.

The Future: This project is still in its infancy. We have begun testing prototypes with children and are exploring funding options. Fortunately, NetLogo and Tern speak a common language—the Java programming language. However, a much more important commonality is a shared vision and pedagogical orientation that we hope will result in a fruitful collaboration.

Authors

• Michael S. Horn, Northwestern University

• Uri J. Wilensky, Northwestern University