Unit 5 Defining Attributes of 2-D and 3-D Shapes

In Unit 5 students will:

  • Distinguish between defining attributes (e.g., triangles are closed and three-sided) versus non-defining attributes (e.g., color, orientation, overall size); build and draw shapes to possess defining attributes.
  • Compose two-dimensional shapes (rectangles, squares, trapezoids, triangles, half-circles, and quarter-circles) or three-dimensional shapes (cubes, right rectangular prisms, right circular cones, and right circular cylinders) to create a composite shape, and compose new shapes from the composite shape.
  • Partition circles and rectangles into two and four equal shares, describe the shares using the words halves, fourths, and quarters, and use the phrases half of, fourth of, and quarter of.  Describe the whole as two of, or four of the equal shares.  Understand for these examples that decomposing into more equal shares creates smaller shares. (Students do not need to learn formal names such as "right rectangular prism.")

By the end of Unit 5 your child should be able to answer the following questions:

  • How can I use attribute language to describe a two-dimensional shape?
  • How can I use attributes to compare and contrast different shapes?
  • How do I compose and/or decompose a two or three-dimensional shape?
  • How do I build shapes with defining attributes?
  • How do I draw shapes with defining attributes?
  • How can I divide circles or rectangles into halves or quarters?

The following videos explain some of the topics in Unit 5.

  • Polygon Song

  • What is a Polygon?

  • 3D Shape Song

  • Symmetry

  • To Play an Identifying Polygons Game at Sheppard Sortware
  • To Play a Lines of Symmetry Game at Sheppard Software 
  • To Play an Identifying Shapes Game at Sheppard Software