Looking At Things From Different Angles
This lesson will introduce students to angles using a resource of Shodor Education Foundation, Inc. Permission has been granted for the use of the materials as part of the workshop "Interactivate Your Bored Math Students."
A lesson plan for grade 6 Mathematics
Learning outcomes
Students will:
- define and give examples of alternate interior, alternate exterior, adjacent, and corresponding angles
- explain how to fill out the chart in the exploration questions
- discuss parallel and perpendicular lines
- define and show examples of right angles, obtuse angles, and acute angles
From http://www.shodor.org/
Teacher planning
Time required for lesson
105 Minutes
Materials/resources
- Graph Paper
- Pencil
- Linguine
- Protractor
- Beans: 4 for each student
- Popcorn Kernels: 4 for each student
- Angles Worksheet
- Ruler
- About 2 yds of string
- 2 yard sticks or meter sticks
Technology resources
Color monitor with access to the Internet for each student
Either a computer lab with Internet access or a one computer classroom with an Internet connection.
Check to make sure the browser supports the Shodor applets.
Pre-activities
Preceding this lesson student should be familiar with the following terms:
- acute angles
- obtuse angles
- right angles
- parallel lines
- perpendicular lines
- intersecting lines
Activities
I use 4 different activities that combine physical, visual, written and technological aspects to teach and reinforce this concept.
Activities 1, 2 & 3 could be done in 1 hour. Activity 4 and the Assessment could be done in 45 minutes. The entire lesson would probably be best done over 2 days.
ACTIVITY 1:
- Each student will have 3 linguine noodles (any flat long noodles will work) and 2 different beans, 4 of each.
- They will place 2 noodles on their desk parallel to each other. They will place the third noodle so that it intersects both the lines, but not perpendicular.
- Instruct them to take 4 beans and place them in all the acute angles. Then take the 4 popcorn kernels and place them in all the obtuse angles.
- They should now have 1 kernel/bean in each of the 8 angles.
- This is the A-HA! moment; ask them to make some observations about what they can see.Hopefully they will notice that the acute angles are “vertical”, they may notice that outside top left and outside bottom right are the same bean/kernel (alternating exterior angles). At this point I am not overly concerned about terminology more about introducing the concept, although I would say the terms as they discover them. Keep prompting until all the concepts have been discovered. (It is up to your discretion what you do with the manipulatives, some students may want to eat them)
ACTIVITY 2:
- Students are still in seats, at desks. Choose 2 students to hold the string midway across the room. Then choose 4 students to form boundaries on both ends of the rope. What you want this to simulate is a volleyball court, the string being the net, and the rulers being the boundaries.
- The net/string is the transversal and the sticks are the parallel lines. This is a good time to start reinforcing concepts. Lead them through a brief discussion about choosing sides for teams. “You go here, You go there…alternating.”
- Once they have caught on ask where they think the interior part of the court is and where the exterior might be.
- Finally place 2 students as alternating exterior people, continue until you have covered all possible combinations. They should remember that when they did the noodles those angles were equal.
ACTIVITY 3:
- vertical angles: <1 = <4
- alternating interior angles
- alternating exterior angles
- adjacent angles
- corresponding angles
- supplementary angles (review)
They may ask the people in their group if they get stuck.
- The student will need to have access to a computer for this activity. Go to Angles. Explain, model, and demonstrate the assignment to the students.
- Have them go through this a number of times while you go around the room and check their scores, when you are convinced they have mastered the concepts, proceed to the assessment worksheet.
Assessment
When students have shown that they understand the concepts to your satisfaction, hand out the Angle Worksheet.
Students need to be aware that there are duplicates in some of the boxes. It would be beneficial to point some of these out before you begin.
The most important part of this assessment is to find out if the student has grasped the major concepts: alternating interior angles, alternating exterior angles, vertical angles, & corresponding angles.
There are a total of 216 entries on this sheet.
I would be looking for mastery, competency, adequate (but lacking), and needs attention. Based on that I would assign students to groups and the following day start the lesson with a review that would allow the students to work together to fill in the gaps.
- 95-100% = mastery
- 75-95% = competency
- 50-75% = adequate (but lacking)
- less than 50% = needs attention
Because it is a chart it is fairly visible to tell what percentage of the chart is complete.
Supplemental information
None.
Related websites
Angles Activity
http://www.shodor.org/interactivate/activities/angles/
Angles Worksheet
http://www.shodor.org/interactivate/media/worksheets/5.pdf
Angles Lesson
http://www.shodor.org/interactivate/lessons/Angles/
Angles Discussion
http://www.shodor.org/interactivate/discussions/Angles/
Comments
At some point after activities 1 or 2 I would have a brief discussion about why this might be important to someone.
North Carolina Curriculum Alignment
Mathematics (2004)
Grade 6
- Goal 3: Geometry -The learner will understand and use properties and relationships of geometric figures in the coordinate plane.
- Objective 3.01: Identify and describe the intersection of figures in a plane.
- Objective 3.04: Solve problems involving geometric figures in the coordinate plane.



