Lesson 1: Draw, Points, Lines and Rays

Domain: Geometry

Cluster: Draw and identify lines, and angles and classify shapes by properties of their lines and angles.

4.G.1 Draw points, lines, line segment, and rays, angles (right, acute, obtuse) and perpendicular and

parallel lines. Identify these in two dimensional figures.

This lesson is a series of 1 of 8 lessons. (This lesson addresses drawing points, lines, line

segments and rays. Identifying them in shapes).

Coherence:

Previous Grade 3: Reason with shapes and their attributes.

1. Understand that shapes in different categories (e.g., rhombuses, rectangles, and others) may share attributes (e.g., having four sides), and that the shared attributes can define a larger category (e.g., quadrilaterals). Recognize rhombuses, rectangles, and squares as examples of quadrilaterals, and draw examples of quadrilaterals that do not belong to any of these subcategories.

Now Grade 4: Draw and identify lines and angles, and classify shapes by properties of their lines and angles.

1. Draw points, lines, line segments, rays, angles (right, acute, obtuse), and perpendicular and parallel lines. Identify two-dimensional shapes.

Next Grade 5: Classify two-dimensional figures into categories based on their properties.

3. Understand that attributes belonging to a category of two-dimensional figures also belong to all subcategories of that category. For example, all rectangles have four right angles and squares are rectangles, so all squares have four right angles.

STANDARDS FOR MATHEMATICAL PRACTICE TO BE EMPHASIZED 5. Use appropriate tools strategically.

6. Attend to precision

Lesson Objectives: I CAN statements

I can draw points, line segments and rays and identify two dimensional figures.

Essential Questions

How does understanding lines and angles help you identify geometric shapes?

Materials: pencils, scissors, math journal

Introduction: Today we will create lines, and rays and identify these in two dimensional figures. In the

third grade you learned to understand that shapes in different categories (e.g., rhombuses, rectangles,

and others) may share attributes (e.g., having four sides), and that the shared attributes can define a

larger category (e.g., quadrilaterals). By 4th grade you will begin to learn that a vertex is where angles

are formed.

Vocabulary:

point - a location in space

line - connects two point via the shortest path and continues indefinitely in both directions

line segment part of a line between two points

Procedure:

1. Ask scholars What can you recall at these

1. Write terms on the board and ask students what they know about the terms point, line and look at

examples.

NEW VOCABULARY: line, line segment, endpoint, point, ray.

Ask students what they recall about these words. For example, they might remember that rays can be

used to form angles.

2. Ask students to explain what they know about lines and rays using a KWL Chart. (teacher should

display the KWL and write down student responses, in the first portion you only want to focus on what

the students know)

3. Ask students what prior experiences they have with the words lines, rays, and line segments and how

they were used in earlier grades.

4. These are the things you already recall, now lets think about things you want to learn. (Teacher

should request specific questions about the content the students need to learn) Appropriate questions

should include: Why does a ray have an endpoint? Why does a line go on forever?

5. Later will students will answer the questions generated by their peers at the end of the lesson.

(Teacher will type up the questions to distribute to students at the end of the lesson from the KWL

Chart.)

Pedagogy/Content: Students should place information in math journals

Vocabulary: line- goes on forever in both directions line segment-is a part of a line with two endpoints endpoint-the point at the beginning of a ray point- an exact location represented by a dot ray-has one endpoint that goes on forever in one direction

6. Draw examples of lines on the board and show different lengths of lines.(the teacher should

emphasize that a line goes on forever)

7. Explain that a line is part of a ray. A ray starts at an endpoint and goes on forever in one direction.

8. Ask: Using a KWL? Have students pose questions about what they want to learn about the new

vocabulary.

Small Groups

Ask small group of students to draw examples of the new words on the board. Have a second group of

students come to board and label the drawing using their new vocabulary words.

A ray is named by its endpoint and one other point. An angle is named by the common endpoint of its

rays, called the vertex of the angle.

Have student use toothpicks, pieces of straw, or pipe cleaners to create different shapes. Have them

label the parts of the shape using the mathematical conventions (line segments, points, etc.)

Conceptual Understanding:

Explore: What do you need to know in order to draw points, lines and rays?

"discuss students prior knowledge of points, lines, and rays."

Teacher: .Draw a point on the board. Label the point you drew

Do you think you can draw and identify other types of geometric figures such as lines, line segments,

and rays?

Real World Example:

Mackenzie drew the figure shown. Identify the figure she drew.

The figure extends in opposite directions. The arrows indicate that it extends without

ending. It is a line.

This line labeled with point X and point Y. There are different ways to represent this line,

such as line XY or XY.

So, Mackenzie drew line XY or XY.

Math Talk:

How are lines and line segments alike? How are they different? Sample answer: Both lines and line segments consist of points. A line extends forever in both directions. A line segment is part of a line, but it has two endpoints.

Students can break into differentiated group based on their responses.

Basic Hands-On Activity

Materials: index cards, markers Guide students to draw and label an example of a line, line segment, ray and endpoint on 4 cards. On each card with a different color marker, have students identify the figure with its name. With a third color, have students identify the figure with its symbol and letters. Tell students to keep card to refer to throughout unit.

Proficient Hands-On Activity

Materials: index Draw and label an example of a line, line segment, ray and endpoint on 4 cards. On 4 cards identify each figure with its name. On another 4 cards identify each figure using symbols and letters. Shuffle cards and match up each cards with the appropriate symbol and letters.

Accelerated Hands-On Activity

Materials: grid paper and markers Using grid paper, draw a picture of a real world object using only line segments, lines, endpoints, and rays. Create a key in which each word represented its symbol is a different color.

Technology: Students can identify lines, line segments and rays.

http://www.ixl.com/math/grade-4/lines-line-segments-and-rays

Formative Assessment

Quick write: Explain the difference between a line and a line segment in Math Journal

A line extends forever in two directions; a line segment is a part of a line, but has two endpoints.

Line, Line Segments, and Rays...

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