Identifying 2D and 3D Shapes

Learning how to identify two and three dimensional shapes is a second grade, Common Core math skill: 2.G.1. Below we show three videos that demonstrate this standard. Then, we provide a breakdown of the specific steps in the videos to help you teach your class.

Prior Learnings

Your students should be familiar with working with shapes, drawings, “manipulatives” and real-world objects.. In the first grade, students will have described and classified shapes based on their geometric attributes (1.G.1). Additionally, your students will have learned to distinguish between defining and non-defining attributes. 

Future Learnings

Eventually, your students will apply these second grade concepts to further their understanding in future classes. Students will be able to connect the concept of equal groups to multiplication (3.OA.1). Students will be able to connect different shape categories and form relationships between categories and subcategories (3.G.1). Additionally, your students will understand how to use written fraction notations (3.NF.1, 3.G.2). 

Common Core Standard: 2.G.1 - Recognize and draw shapes having specified attributes, such as a given number of angles or a given number of equal faces

Students who understand this principle can: 

1. Classify two-dimensional shapes as flat or plane shapes and three-dimensional shapes as solid shapes. 
2. Identify defining attributes of 2D and 3D shapes like angles, faces, and sides.
3. Recognize that attributes are used to classify 2D and 3D shapes.
4. Identify shapes from the specified attributes.
5. Draw shapes based on given attributes. 
6. Identify various shapes such as “triangles, quadrilaterals, pentagons, hexagons, and cubes.”

2 Videos to Help You Teach Common Core Standard: 2.G.1

Below we provide and breakdown three videos to help you teach your students this standard.

Video 1: Naming Parts of 2D and 3D Shapes

The video discusses both two-dimensional and three-dimensional shapes. It shows the basic qualities of 2D and 3D shapes, helping students identify and count those qualities.

The video starts by explaining that flat shapes are two dimensional (2D) and have length and width. Objects are three dimensional (3D); they have length, width, and height. 

1. 2D shapes are made of angles and lines.
2. An angle is the space inside a corner.
3. Where 2 sides meet, it is called a vertex.

Next, the video asks viewers a question: How many sides and vertices are on the rhombus?

1. There are 4 sides.
2. There are 4 vertices.

Then, the video explores 3D shapes, listing the three parts they have: faces, edges, and vertices.

1. A face is a single flat surface. 
   a. A cube has 6 faces.
2. An edge is where 2 faces meet.
   a. A cube has 12 edges.
3. A vertex is where 2 or more lines join together.
   a. A cube has 8 vertices.

The video ends by reminding students that the words to know for 3D shapes are faces, edges, and vertices.

Video 2: Finding Parts of 3D Shapes

Here we provide two Boddle videos covering the math standard 2.G.1. The first video discusses 3D shapes, and the second video covers how to identify 2D shapes.

The video begins by explaining that three-dimensional shapes are solid figures. It then asks students to think of a three-dimensional object they see everyday: a book, a can, a box.

Then, it explains that there are 3 ways students can use to identify the type of 3D shape.

1. Counting the number of vertices.
   a. Vertices are corners where 2 line segments meet.
   b. A cube has 8 vertices or corners.
2. Counting the number of faces.
   a. Faces are the flat surfaces of a shape.
   b. A cube has 6 faces.
3. Counting the number of edges.
   a. Edges are the line segments where 2 faces meet.
   b. A cube has 12 edges.

Next, the video looks at a triangular prism, asking the students how many faces, vertices, and edges it has.

1. It has 5 faces.
2. It has 6 vertices.
3. It has 9 edges. 

Then, Boddle gives students a chance to practice counting the number of faces, edges, and vertices on their own. The example is of a rectangular prism, which has 6 faces, 8 vertices, and 12 edges.

Video 3: Identifying 2D Shapes

The video begins by explaining that two-dimensional shapes are shapes that are flat and shows examples of 2D shapes. Boddle discusses how students can describe these shapes by the number of sides they have and their angles.

Next, Boddle looks at a square to demonstrate how to find the number of sides and angles.

1. The square has 4 sides.
2. The square has 4 angles.
3. So a square can be described by saying it has 4 sides and 4 angles.

After, two examples are shown to help students understand the concept more. The first example counts along with the students, and the second one has the students identify the correct shapes based on the given criteria.

1. The first example is of an octagon.
   a. It has 8 sides.
   b. It has 8 angles.
2. The second example asks students to find the pentagon.
   a. A pentagon has 5 sides and 5 angles.
   b. The third shape is the pentagon.

 Want more practice?

 Give your students additional standards-aligned practice with Boddle Learning. Boddle includes questions related to Comparing and Measuring Lengths plus rewarding coins and games for your students to keep them engaged. Click here to sign up for Boddle Learning and create your first assignment today.

 *Information on standards is gathered from The New Mexico Public Education Department's New Mexico Instructional Scope for Mathematics and the Common Core website.