In Part 1 of this report, the committee has presented the case for teaching spatial thinking to all students. It is important to understand what spatial thinking is and how it works. It is equally important to understand how expertise in spatial thinking develops in general and differently among different people. Both sets of understandings are necessary precursors for developing systematic educational programs to teach American students how to think spatially. In Part II of this report, the committee shows how support systems, particularly those that are technologically based, can facilitate the teaching and practice of spatial thinking. Chapter 7 reviews a series of high-tech support systems for spatial thinking, providing a context for the detailed analysis of GIS. Chapter 8 presents a critical analysis of the design, implementation, and use of GIS. The current use and potential development of GIS are evaluated in terms of the ten general criteria for the design of a support system and in terms of the three specific characteristics of a support system for spatial thinking. Chapter 9 summarizes the findings of the analysis of GIS. In Chapter 10, the committee presents recommendations directed at the goal of fostering spatial thinking in general and at the specific goal of enhancing the design and implementation of one support system, GIS.