If you are citizen of an European Union member nation, you may not use this service unless you are at least 16 years old.
You already know Dokkio is an AI-powered assistant to organize & manage your digital files & messages. Very soon, Dokkio will support Outlook as well as One Drive. Check it out today!

1-GM-1-2

Page history last edited by Tashe Harris 6 years, 2 months ago

1.GM.1.2 Compose and decompose larger shapes using smaller two-dimensional shapes.

In a Nutshell

First Grade students will compose (combine) and decompose (take apart) two-dimensional figures such as triangles, squares, rectangles, circles, and compose two-dimensional shapes (rectangles, squares, trapezoids, triangles, to create a composite shape, and compose new shapes from the composite shape.For example: decompose a regular hexagon into 6 equilateral triangles or two trapezoids and another example could be a trapezoid into 3 triangles.

Student Actions	Teacher Actions
Develop deep and flexible conceptual understanding as students use pattern blocks and other materials to compose and decompose shapes in a variety of settings. Teachers can provide students with cutouts of shapes and ask them to combine the cutouts to make a particular shape. Composing with squares and rectangles and with pairs of right triangles that make squares and rectangles is especially important for future geometric thinking. Develop accurate and appropriate procedural fluency as students build larger shapes from smaller shapes. Develop the ability to communicate mathematically by using mathematical language to describe shapes using characteristics that include the number of sides and vertices (corners). Students will develop a productive mathematical disposition as they investigate and predict the results of putting together and taking apart two-dimensional shapes.	Implement tasks that promote reasoning and problem solving by providing opportunities for student to explore, see and feel, compose and decompose, and to make observations with a variety of materials. As students work with pattern blocks to compose and decompose shapes they will be able to emphasize properties of shapes rather than simple identification. Facilitate meaningful mathematical discourse by encouraging student discussions about how or why other shape formations could also be correct will enrich student understanding. Once students are familiar with the language, they are able to make-up their own questions. Please note there are some examples that could have multiple correct answers. Answers are correct as long as students are able to justify them. Posing purposeful questions and Facilitate discussion in order to engage students in the learning process. What can you tell me about this shape? What shape can you use to make ____ a different way? How are these shapes alike and different? How can they be put together or taken apart?
Key Understandings	Misconceptions
Recognize, name, build, draw, compare, and sort two-dimensional shapes, such as triangles, squares, hexagons, and trapezoids. Describe attributes and parts of two-dimensional shapes, vertices, corners, and number of sides. Investigate and predict the results of putting together and taking apart two-dimensional shapes for example: decompose a regular hexagon into 6 equilateral triangles or two trapezoids and another example could be a trapezoid into 3 triangles.	The shape changes as the size or location changes. An equilateral triangle is the only kind of triangle.