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Spatial reasoning is a skill that needs to be developed in students as it isimportant in geometry for determining total surface areas and volumes of 3-dimensional shapes (Liedtke, 1995). Simply teaching children the formulae, in this case for finding total surface areas, can limit them in understanding mathematics conceptually (Bonotto, 2003). As pointed out in the NCTM Principles and Standards (2000): Some students may have difficulty finding the surface area of three-dimen-sional shapes using two-dimensional representations because they cannot visualize the unseen faces of the shapes. Experience with models of three-dimensional shapes and their two-dimensional “nets”1 is useful in such visualization … Students should build three-dimensional objects from two-dimensional representations (p. 237). Helping students establish a relationship between the total surface area of a three-dimensional solid and the area of a two-dimensional net should help them in understanding total surface area conceptually. In this article the challenges pre-service secondary school teachers faced in trying t