Skip to main content

Tangible Flags

Become a Kidsteam kid

If you are interested in getting your child involved in kidsteam, please contact Dr. Allison Druin at

Tangible Flags are designed to support and encourage children to concurrently explore, collaborate and construct digital artifacts while they are immersed within mobile, hands-on environments, such as field trips.  Children can use Tangible Flags to mark interesting points as they explore in an open environment.  They can then create notes or drawings on a mobile computer and attach the digital information to the Tangible Flag with a physical action, by placing the computer over the flag.  When they discover a Tangible Flag placed by another child, they can access the digital information with the same action and annotate that information in a shared space.


Field trips give children an opportunity to explore an authentic context.  Children are typically encouraged to observe and take notes while they explore their surrounding environment.    This is followed by classroom activities where the children work together to create reports or posters to represent the knowledge gained.  Both activities are important for learning, yet they occur in separate spaces and at different times. During the field trip, children busy exploring may lack awareness of their classmates’ activities, resulting in lost opportunities to collaborate.  Children in a classroom are removed from the original experience and cannot explore further. Tangible Flags was created to bridge the gap between these two activities.


  • To enable children to embed and access digital information directly within the context of the real world, using a physical interaction.
  • To support children’s awareness of the exploration and artifact creation activities of others while they move about an open environment.
  • To provide children with concurrent access to a joint digital space for the collaborative construction of a knowledge artifact.


A physical connection to digital information is obtained by computationally enhancing Tangible Flags to be recognized by a computer.  This is achieved with Radio Frequency Identification (RFID), a common commercial sensor often used in inventory control.  The software interface design is focused on supporting collaboration in a mobile environment.  The two key elements for collaboration in such environments are awareness and concurrent interaction.  Awareness of other’s efforts has been recognized in research literature as a critical issue in supporting collaboration.  This is especially true in a mobile learning environment, where awareness can suffer because children are focused on individual exploration.  Concurrent interaction is also important in this environment for the same reason.  Activities that require excessive waiting on others are soon discarded in favor of immediate exploration.

Scanning Tangible Flags

RFID tags are passive devices consisting of flexible copper traces printed on paper, each with its own unique ID.  Tangible Flags are built by embedding a RFID tag inside a flag made of art materials (Figure 1 and 2). A RFID scanner is attached to a mobile computer.  Placing the scanner in a prominent location makes its use clear to younger children.  The scanner has a color that matches that of flags used by the child (Figure 3).

Tangible Flags showing RFID tag

Figure 1

Large Tangible Flag

Figure 2

Tablet PC with RFID scanner

Figure 3

The simple, physical interaction of placing the scanner near the Tangible Flag opens the shared space in the software interface associated with that flag (see Software Interface).  Once discovered, the shared space can later be accessed through the software interface from any location, but the original discovery experience provides a mental association to the real world context.  This may aid children in relating their current thought process to the digital information or to again locate the Tangible Flag in the physical space.

Supporting Awareness

Tangible Flags are visually apparent and discovering a flag gives a clear indication that another child has explored the area and found something interesting.  Children also know their peers have left notes attached to the Tangible Flag and the color of the flag indicates the author.  A child can easily and immediately turn this awareness into access to the digital information by scanning the Tangible Flag, making it straightforward to initiate collaboration.  This collaboration occurs in a relevant context as it is situated by the Tangible Flag.

Software Interface

The software interface is designed to support children’s collaboration (Figure 4).  The large working area (Figure 4 – pointer 1) is a shared space where children can concurrently draw pictures or leave notes associated with a particular Tangible Flag (as noted by background color and number in upper left corner).  The author is indicated by the color of the ink, which matches the color of their computer and Tangible Flags.  The flag thumbnail area (Figure 4 – pointer 2) shows a thumbnail image of all Tangible Flags a child has discovered and scanned.  Selecting a thumbnail activates the working area for that Tangible Flag.  Animation is used to swap pages between the thumbnail area and the working area.  Scanning a Tangible Flag with the RFID reader also selects its page; children can use either interaction to access different Tangible Flag pages.

There is an always present instant messaging space called ScratChat (Figure 4 – pointer 3) that is not associated with any Tangible Flag.  Any writing in this space temporarily appears in the ScratChat space of all computers.  This emphasizes its nature as a message space, not a note taking space, and keeps the space clear for future messages.

The software interface can also display aggregate information based on the children’s inputs.  For instance, in the interface shown in Figure 4, children can vote whether the flagged object fits any of the listed categories (seen in the top of the working area).  Summary results for all flagged objects are displayed in the ScratChat area (left side).

GUI Interface

Figure 4

Design Process

We developed Tangible Flags working with both our in lab design partners (children aged 6-11) and with the kindergarten class of 2005 at the CYC (Center for Young Children), the university’s research preschool.  We observed classroom field trips and participated in mock field trips using low tech prototypes to experiment with Tangible Flags.  During our summer camp with our lab design partners, we did several scavenger hunts, both indoors and outdoors, using the high tech prototype.  Numerous design ideas, including the color coding flags and computer covers, and changes to the size of the Tangible Flags, are a result of these Cooperative Inquiry sessions.


Case study at Rock Creek National Park

We conducted a case study at Rock Creek National Park using an existing park program adapted for the use of the Tangible Flags technology.  Park visitors (children and their parents) participated in a forest walk scavenger hunt along a 1/4 mile trail.  During the walk, children explored independently while using Tangible Flags to mark scavenger hunt items found along the trail and leave notes or draw pictures.

The park ranger did not accompany any of the children; instead she moved along the trail to see what the different children did. The ranger was given a tablet computer that was running in a special ‘observer’ mode, which has a thumbnail in the flag area for all Tangible Flags. Without scanning, the ranger could see all the notes written by each child and could write questions or responses on the Tangible Flag pages (the ranger’s writing showed as black). In addition, the ranger had placed two Tangible Flags along the trail before the activity began, on which she had written some questions.

The pages below illustrate how children used the Tangible Flags technology in situate digital information in the environment and collaborate with each other and the park ranger (Figures 5, 6, 7, 8).

Notes left on a pond

Figure 5

Notes left on a large Chestnut Oak tree

Figure 6

Notes left at a Pawpaw tree

Figure 7

Notes left at a Devil's Wlaking Stick tree.

Figure 8

Comparative Study with a Kindergarten Class

We have recently finished a study with the kindergarten class of 2006 at the CYC.  The classroom participated in a number of observation and note taking activities around their school.  Half of the classroom used the Tangible Flags technology and half used paper notes (Figure 9).  The results of this study are not yet available.

Paper used for comparison to Tangible Flags

Figure 9


Gene Chipman, PhD candidate in Computer Science, Human-Computer Interaction Lab.

Dr. Allison Druin, Associate Professor, College of Information Studies,  Human-Computer Interaction Lab.

Jerry Alan Fails, PhD student in Computer Science, Human-Computer Interaction Lab.

Mona Leigh Guha, PhD student in Education, Human-Computer Interaction Lab.

Sante Simms Research staff, Human-Computer Interaction Lab.


Published in proceedings of Interaction Design and Children 2005: Collaborative Creation of Knowledge Artifacts in an Outdoor Environment for Young Children

Published in proceedings of Interaction Design and Children 2006:  A case study of Tangible Flags: A collaborative technology to enhance field trips.



Tech Reports
Video Reports
Annual Symposium

Seminars + Events
HCIL Seminar Series
Annual Symposium
Events Archives
Job Openings
For the Press
HCIL Overview
Collaborators + Sponsors
Collaborating Groups + People
Academic Visitors
Industrial Visitors
Active Sponsors
Become a Sponsor
Our Lighter Side
Join our Mailing List
Contact Us
Visit Us
Faculty/ Staff/ Admin
Ph.D. Alumni
Past Members
Research Areas
Design Process
Digital Libraries
Physical Devices
Public Access
Research Histories
Faculty Listed by Research
Project Highlights
Project Screenshots
Online Tech Reports
Video Reports
Studying HCI
Graduate Studies in HCI
Visiting Scholars
Class Websites

Web Accessibility