5.G.3. 4Understand that attributes belonging to a category of two- dimensional ﬁgures also belong to all subcategories of that category. For example, all rectangles have four right angles and squares are rectangles, so all squares have four right angles. Classify two-dimensional ﬁgures in a hierarchy based on properties.
Teachers need to understand both of these aspects of geometry to help a student grow. Spatial senses include the inability to visualize mentally objects and spatial relationships - to turn things around in your mind.
The four goals of geometry are Shapes and Properties, Transformation, Location, and Visualization.