## Tracing and Drawing

In this lesson, students continue to discuss attributes of triangles. They trace and draw triangles individually. Students recognize objects in their environment that are shaped like triangles and explain to the class how they recognized the shape.

Review the previous lesson by encouraging students to recall the properties of triangles. Place the attribute triangles on tables for students to explore independently. This exploration helps satisfy the students’ curiosity and builds on their initial experiences with the properties of triangles. Invite students to ask questions of you and each other.

After students adequately explore the shapes, give them copies of the My Triangles Activity Sheet. Instruct them to work individually to trace the triangles printed on the sheet and then trace the attribute triangles found in the bag onto a blank sheet of plain copy paper.

Demonstrate how to hold the attribute block with one hand while tracing with the other. If students have difficulty with this task, they can work in pairs with one holding the triangle while the other draws, and then switching roles. To make tracing easier, students can also tape the attribute triangles to the paper or place the paper on top of a triangle that is taped to the table and use a crayon to rub over the triangle. After the students complete at least two tracings or rubbings of triangles, ask them to do free-hand drawings of triangles on another sheet of paper.

When students complete their drawings, have them look through books or magazines for triangles or have them sort collections of shapes that you have placed in bags.

To close this lesson, ask each student to identify a triangle in the room. Then have students share with the class where they found triangles and how they knew the objects were triangles.

- Attribute blocks
- Plain copy paper
- My Triangles Activity Sheet

**Assessment Options**

- Record your observations of students’ work and comments on the teacher resource sheet Class Notes.
- For homework, have students draw a picture of an object that has a triangle as a component and ask an adult to label the picture for them. Students will need to bring this to class the next day.

**Extension**

Move on to the next lesson,Geoboards.

**Questions for Students**

1. Can you tell me how many sides each triangle has?

[They have three sides.]

2. Can you find a triangle and count its sides?

[Students should be able to locate a triangle and count three sides.]

3.Would you practice drawing a triangle in the air by watching me draw one in the air?

[Watch students as they demonstrate this for you.]

4. When you trace a triangle, what will you need to remember?

[I have to keep the triangle still.]

5. When you draw a triangle without tracing, what do you need to remember?

[A triangle’s sides are straight. A triangle has 3 sides and 3 corners.]

6. How many triangles can you find in the classroom without leaving your space? Can you describe the location of the triangles so that your classmates can find them?

[Student responses may vary.]

7. What are some words you might use to describe the triangles found in the room?

[Flat, pointy, smooth/straight.]

**Teacher Reflection**

- Were students able to relate today’s discussion to what they learned in the previous lesson?
- Did I address problematic examples, such as pizza or pie slices, that do not have three straight sides and three closed corners?
- Were there adequate examples of triangles in the classroom for students to locate? If not, what additional objects can I bring in to show different types of triangles (acute, obtuse, scalene)?

### Three Sides

### Geoboards

### Making Virtual Triangles

### Learning Objectives

Students will:

- Identify and describe triangles.
- Draw triangles.
- Locate triangles in their environment.

### NCTM Standards and Expectations

- Recognize, name, build, draw, compare, and sort two- and three-dimensional shapes.

- Recognize geometric shapes and structures in the environment and specify their location.

### Common Core State Standards – Mathematics

-Kindergarten, Geometry

- CCSS.Math.Content.K.G.A.1

Describe objects in the environment using names of shapes, and describe the relative positions of these objects using terms such as above, below, beside, in front of, behind, and next to.

-Kindergarten, Geometry

- CCSS.Math.Content.K.G.A.2

Correctly name shapes regardless of their orientations or overall size.

-Kindergarten, Geometry

- CCSS.Math.Content.K.G.B.4

Analyze and compare two- and three-dimensional shapes, in different sizes and orientations, using informal language to describe their similarities, differences, parts (e.g., number of sides and vertices/''corners'') and other attributes (e.g., having sides of equal length).

Grade 2, Geometry

- CCSS.Math.Content.2.G.A.1

Recognize and draw shapes having specified attributes, such as a given number of angles or a given number of equal faces. Identify triangles, quadrilaterals, pentagons, hexagons, and cubes.