Unit 5

Identifying, Composing, and Partitioning Shapes


Grade 1




Description:  Students think about attributes of shapes and practice composing and decomposing geometric shapes. This provides important “internalization time” for students between two intense number-based units to build their confidence before they return to place value and operations.


Louisiana Student Standards for Mathematics (LSSM)

Instructional Outcomes



Tell and write time and money.


Tell and write time in hours and half-hours using analog and digital clocks. Recognize and identify coins, their names, and their values.





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) and 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. (Note: Students do not need to learn the formal names such as right rectangular prisms.)




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 shares.  Understand for these examples that decomposing into more equal shares creates smaller shares.



Enduring Understandings:


·         Two-dimensional and three-dimensional shapes can be identified based on defining attributes of the shape.

·          Two-dimensional and three-dimensional shapes can be used to compose new shapes. 

·         Students will decompose two-dimensional and three-dimensional shapes to create new shapes, with a focus on decomposing circles and rectangles into halves and fourths.



Essential Questions:


·         How can I tell about shapes? 

·         Where can shapes be found in my world?

·         How can I sort and tell about shapes?

·         How are shapes alike?  Different?

·         How can I use two-dimensional and three-dimensional shapes to compose new shapes?