Spatial thinking -- Space and language -- How important is spacial thinking? -- How do spatial concepts develop? -- Introduction -- Piaget's theory -- Criticisms of piaget -- Van hiele levels -- Shape recognition -- Developing an awareness of the properties of shape -- Fitting shapes together -- Lines and angles -- How do children form misconceptions about space? -- 2-dimensional representations of 3-dimensional space -- Development of reference systems -- Conservation -- Transformation geometry -- Measurement -- Number -- Language: words and symbols