Participatory Simulations: Using Computational Objects to Learn about Dynamic Systems

Vanessa Colella, Richard Borovoy, and Mitchel Resnick

MIT Media Laboratory
20 Ames Street, E15-320C
Cambridge, MA 02139 USA
+1 617 253 5988
{vanessa, borovoy, mres}


New technology developed at the MIT Media Laboratory enables students to become active participants in life-sized, computational simulations of dynamic systems. These participatory simulations provide an individual, "first-person" perspective on the system, just as acting in Hamlet provides such a perspective on Shakespeare. Using our Thinking Tags, small, name-tag sized computers that communicate with each other via infrared, we add a thin layer of computation to participant’s social interactions, transforming a group of people into participants in a dynamic simulation. Participants in these simulations get highly engaged in the activities and collaboratively study the underlying systemic model.


Children, education, CSCL, augmented reality.


In recent years, there has been a growing movement in the CHI community to bring computation into everyday physical objects [2,4,8]. As part of the Things That Think Consortium at the MIT Media Lab, members of the Epistemology and Learning Group are studying how traditional children’s objects like balls, beads, and blocks can be imbued with computation. Through direct manipulation of these new objects, children can gain an understanding of "systems concepts" like feedback and emergence—concepts often viewed as too complex for kids.

This paper describes work that builds on previous work of bringing computation to objects in the real world. However, where much of the previous work focuses on how individuals interact with computationally-augmented physical objects, this work extends in the direction of Computer Supported Collaborative Learning (CSCL). We have developed a family of Thinking Tags—small, wearable computers that add computation to social interactions.

Using the Thinking Tag technology [1], we create participatory simulations, in which fifteen to seventy-five people are each given a Tag to wear. As people interact, their Tags also interact, using infrared communication. Since the Tags are fully programmable, we can use them to simulate a variety of dynamic systems. For example, the Tags can be programmed to facilitate the human-scale simulation of an epidemic spreading through a population.


During the past ten years, computers have been used increasingly as simulation machines. The widespread popularity of game software like SimCity and SimEarth gives a clear indication of the extent to which simulation has permeated popular culture. Programs like Stella [7], StarLogo [5] and Sugarscape [3] enable users to experiment with complex systems and develop better intuitions about the mechanisms that govern dynamic interactions.

Participatory simulations grew out of an age-old tradition of using role-playing to help people develop personally meaningful understandings of complex or nuanced situations. Role-playing activities are central in the play of young children, as they explore what different possibilities the world affords them, like playing house or playing doctor. In educational circles, role-playing is a common practice in the social sciences where students might be asked to pretend they are politicians or community activists. Resnick and Wilensky [6] built on this idea, using role-playing (or more simply participation) to give people richer understandings of emergent systems.


The Thinking Tags were first used for a Media Lab conference. Each visitor received a Thinking Tag that displayed their name and could be programmed with information about their interests and opinions. When two people interacted, their Tags flashed lights to indicate how much they had in common. [Fig.1] This bit of personal and relational information was a helpful conversation starter.

Fig. 1 Two people meet and their Tags exchange information via infrared signals.


Recently, we modified the Tags and created participatory simulations. Like the original Thinking Tags, these Tags have both an infrared transmitter and receiver, allowing them to dynamically exchange information with all other badges in the simulation. (In these decentralized systems no one badge acts as a server.) The Tags have two output devices, a double digit number pad and five bicolor LEDs. During the simulation the information displayed on the Tags changes, and participants watch the Tags to discover information about themselves and about other players. A resistive sensor port acts as a another input, allowing users to attach small tools to their Tags, enabling them to "dial-in" information or change the program their Tag is running. This carefully chosen set of inputs and outputs provides a rich set of user interactions, both during the simulation and during the subsequent analysis.

As in the original Thinking Tag design, we took care to ensure that the enhanced information display would not interfere with participants’ social interactions. Keeping the technology unobtrusive enabled us to craft human activities that could be integrated with the thin-layer of computation afforded by the Tags.


By wearing the Tags, participants, often high school students, become active agents in a simulation of a dynamic system. For instance, during a simulation of an epidemic, a high school class gets thoroughly engaged as an electronic "virus" jumps from Tag to Tag. [Fig.2] Though every Tag appears the same, one starts the disease propagation, while others may be immune to the disease. The combination of the kids and the Tags forms a sort of digital ecology in which both humans and computers participate. While the Tags keep track of the computational system model, students are free to interact with one another and participate as the system unfolds.

Fig. 2 High school students meet during a participatory simulation.

Following the initial activity, students are challenged to elucidate the disease dynamics. Is transmission of the virus probabilistic? Does the disease have a latency period? Are some people more susceptible than others? During the subsequent collaborative analysis, students use diagnostic "Tool Tags" and small sensor tools to retrieve information from their own Tags, such as who infected them and when. Collaboratively, the students knit together their individual experiences into a coherent understanding of the whole system. Students then restart their Tags and design experiments to test their hypotheses about the viral behavior.

Through the active participation in a simulation like the virus simulation, students become highly invested in understanding the algorithm controlling the disease. Their personal involvement in the simulation makes their experience entirely different from watching an epidemic unfold in a computer model. Bringing the simulation into the students’ world changes their relationship with the technology. For participants, the Tags become part of their own personal space. The unencumbered, thin-layer of technology enables the students to collaboratively study a dynamic system, without battling large monitors, awkward spatial arrangements, and skewed information distribution. Participatory simulations are a new paradigm of computationally-supported learning activities in which technology can not only augment human-human interactions but also can help enrich the understanding that stems from those interactions.


Thanks to Kwin Kramer for designing the new Tag for participatory simulations. This research has been supported by the LEGO Group, the National Science Foundation (grants 9358519-RED and CDA-9616444), and the MIT Media Laboratory's Things That Think and Digital Life consortia.


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