What's My Line?
Students will be able to identify and draw parallel, intersecting, and perpendicular lines.
- Tell students that they will learn about the building blocks of geometry: lines.
- Discuss the three types of lines they will be learning about: parallel lines, perpendicular lines, and intersecting lines.
Explicit Instruction/Teacher modeling(15 minutes)
- Ask for four student volunteers to come up to the front of the room and demonstrate the three types of lines.
- Take out the two pieces of three-foot-long rope or yarn.
- Give each student one end of the rope or yarn to hold.
- Position students so they create parallel lines.
- Ask students to describe the position of the lines.
- State the lines are called parallel lines.
- Reinforce that parallel lines are lines that run side-by-side and never touch.
- Position the students to create intersecting lines that look like an X.
- Discuss how these two lines intersect at a common point.
- Re-position the students to create a plus sign with the lines, creating an intersection with 90 degree angles.
- Discuss the difference in the intersection when 90 degree angles are created.
- Reinforce that these lines are called perpendicular lines.
Guided Practice(10 minutes)
- Display your anchor chart with quadrilaterals.
- Have student volunteers identify the types of lines in the quadrilaterals.
- Be sure to have students identify intersecting, parallel, and perpendicular lines.
- Discuss the characteristics of each type of line.
- Check for understanding.
Independent working time(10 minutes)
- Give each student an index card.
- Ask students to draw a quadrilateral that has parallel lines, at least one pair of perpendicular lines, and one set of intersecting lines that are not perpendicular.
- Have students exchange index cards with a partner and take out their crayons or colored pencils.
- Ask students to put their names in the top right corner of the index card.
- Begin by directing students to underline all parallel lines in the quadrilateral with a red crayon.
- Ask students to circle with blue any perpendicular intersecting lines in the quadrilateral.
- Require students to circle any intersecting lines that are not perpendicular with a green line.
- Collect cards for assessment.
- Create flash cards using the index cards. Have struggling students write one type of line on the front of the index card. On the back of the card, they should draw a corresponding picture and definition of the term. They can use these cards for reference.
- Ask advanced students to create a list of "real life" examples of perpendicular lines, parallel lines, and intersecting lines. They could also label the types of lines in some letters of the alphabet. For an example, the letters H, X, and T have the three types of lines; ask the students to identify them.
- Review index cards and provide written feedback.
- Note any errors and develop an intervention group for students who do not demonstrate mastery.
Review and closing(10 minutes)
- Hand back index cards.
- Ask for several volunteers to come up in front of the class with their index cards.
- Ask students to show their card and discuss what they did and why.
- Check for understanding.