A number of researchers conducted a study to demonstrate an interactive tangible user interface application for learning addition concepts. There were three main addition strategies involved in the implementation of the interactive tangible user interface application for learning addition concepts. These strategies included direct modeling with fingers or physical objects, use of counting sequences, and recalled number facts. The Trackmate System was selected by the researchers from the available systems to conduct the investigations, as it was an open source initiative to create an inexpensive, do-it-yourself system, allowing any computer to recognize tagged objects when placed on a surface. It was also composed of a tangible tabletop system connected to a personal computer running applications that were displayed on a monitor.