Mathematics Lesson Plan - EDFE 3200 D November 2, 2017
Teacher Candidates: Anna Kusnomo, Daiva Ramanauskas, Paulina Salata, Xuewen Yang Subject: Mathematics Grade: 10 Academic Strand: Trigonometry Time: 75 min FRAMEWORK Lesson Specific Expectation: BIG IDEA: Solving Problems Involving the Trigonometry of Right Triangles Solve problems involving the measures of sides and angles in right triangles in real life applications (i.e. in determining the height of an inaccessible object around the school), using the primary trigonometric ratios and the Pythagorean theorem. Mathematical Process Expectations: In this lesson, students will perform processes of: ● Problem solving ● Reasoning ● Selecting tools and computational strategies ● Representing ● Communicating Learning Goals: By the end of this lesson, I will be able to: ● Recall and choose the appropriate trigonometric ratio to calculate the height of an object (Knowledge & Comprehension) ● Relate basic trigonometry ratios to a concrete real-life application (Application) ● Illustrate observations using a diagram (Application) ● Devise a tool and a strategy to measure the angle of elevation and height of an object (Synthesis) ● Compare answers and provide reasoning for discrepancies (Evaluation) Success Criteria: To be successful in this lesson, I will: ● Follow instructions to make a clinometer ● Measure the angle of elevation of a tall object using the clinometer ● Produce a scaled diagram of my investigation ● Label my diagram accurately ● Calculate the height of the classroom wall using the tools I have and the appropriate trigonometric ratio ● Collaborate with my partner to gather data and make meaningful conclusions from it ● Discuss my findings with others using mathematical vocabulary and conventions 1
Mathematics Lesson Plan - EDFE 3200 D November 2, 2017
SEQUENCE Assessment FOR: This can be done before or after Minds On: ● Take up homework from previous class ● Review of “basic trigonometric ratios” (i.e. SOH CAH TOA) as a class ● Review/introduction of the concept of “angle of elevation” and “angle of depression” Minds On: Part 1: FIND YOUR PARTNER
This brief activity acts as a way to both review trigonometric values and partner students up ● Each student will randomly pick a small piece of paper after entering the classroom. (The following table will be printed out and cut into small pieces.) Each piece of paper either has a trig ratio or an actual value written on it. Students will look for their partner by matching the trig ratio with the actual value. They may use a calculator for this activity. sin30o
0.5
tan15o
0.2679
sin10o
0.1736
sin5o
0.0872
tan21o
0.3839
sin35o
0.5736
sin40o
0.6428
sin45o
cos45o
tan12o
0.2126
cos22o
0.9272
cos33o
0.8387
cos55o
0.5736
cos65o
0.4226
cos70o
0.3420
tan80o
5.6713
Part 2: ANGLE OF ELEVATION VS. ANGLE OF DEPRESSION ● With your partner, discuss briefly the difference between angles of elevation and depression Action: ●
Transition: ○ Have you ever thought of how we could measure the height of a wall if we did not have a measuring tape or if it were too high? ○ Would you like to guess what a Clinometer is? ○ Today, we are going to measure the height of our classroom wall using a clinometer.
●
Part 1: MAKING A CLINOMETER (Pairs) ○ Teacher hands out the “Making a Clinometer” instruction sheet (Appendix A) and distributes materials to each pair. This activity should take about 15 minutes. ○ Materials (provided per pair): ■ Protractor template ■ Index paper ■ Straw 2
Mathematics Lesson Plan - EDFE 3200 D November 2, 2017
■ ■ ■ ■ ■ ●
20 cm string Paperclip (as weight attached to the end of the string) Glue Scissors Cellotape
Part 2: USING THE CLINOMETER (Pairs) ○ Once the clinometers are ready to use, send the pairs to different parts of the classroom (or any other room in the school) to measure the height of the room’s wall. Preferably, students measure the height of walls in the same room, so that at the end of the class, pairs can compare results. ○ Teacher will distribute the handout “Using the Clinometer” (A ppendix B) and optionally the pre-designed organizer “Using Trigonometry to Calculate the Height of the Classroom Wall” (Appendix C) prior to the start of the activity. ○ Materials (per pair): ■ Scientific calculator (own) ■ Ruler & stationery (own) ■ Blank paper or pre-designed organizer (provided) ■ Measuring tape (provided - to share with the whole class) ○ Assessment AS: Checklist for Clinometer (Appendix D) This is done by the teacher as students are working on the above activities to check for: ● Student readiness ● Understanding of instructions ● Correct execution of activity ● Collaboration
Consolidation (Assessment AS): Teacher provides opportunity for pairs to share their investigation findings through one of these ways: ○ Volunteers (3-4, preferably those who have approached the problem differently) could be asked to go up to the board and explain their process and solution ○ Pairs pair up with other pairs to compare their results ○ Gallery walk around the classroom ● Teacher will hold a class discussion on the following: ○ Why were some of the results different? (Possible points: taking the wrong reading for angle of elevation, excluding height of the person measuring (at eye level) in calculating the total height, rounding angles or mid-calculations too early in the process, etc.) ○ What would happen to the angle of elevation if you were standing closer or farther away from the wall? Possible Next Step: ●
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Mathematics Lesson Plan - EDFE 3200 D November 2, 2017
Plotting or organizing the class’ data from Activity - Part 2 to identify the range of data values and possible outliers - for further discussion that leads into Data Management. Mid- Unit Assignment (Assessment OF): Now it is your job is to create a scenario where you need to use trigonometry to calculate an object that is either taller than you or higher than you. It is up to you where it takes place. It can take place in your home, your neighbourhood or on Pluto. This is your opportunity to b e creative! What needs to be included: ❏ A description of the scenario. ❏ The question. (ie. Find the height of the tower.) ❏ A diagram of the scenario you are describing. It must be LABELED! ❏ A detailed solution. Show ALL your work and thinking. ❏ A concluding statement that answers the question you posed. ❏ Work must be organized. Accommodations: ● For English Language Learners: ○ Provide an oral component of the instructions (i.e. reading aloud by the teacher) ○ Provide a visual component of the instructions (i.e. visualization on PPT) ● For students struggling in math: ○ Provide pre-designed organizers to document observations, calculations, and results ○ Provide extra time ○ Divide and deliver the task in smaller components ○ Have an Educational Assistant in larger classrooms ● For students in need of breaks (to get up and move around) ○ Minds on activity and the clinometer measuring activity gets the students up and moving while they are learning ● For more advanced students: ○ Introduce a Clinometer app in addition to the Clinometer device students made ○ Provide blank instead of pre-designed organizers to diagram observations
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Mathematics Lesson Plan - EDFE 3200 D November 2, 2017
APPENDIX A Making a Clinometer Did you know? Captain Jack Sparrow used a clinometer in the movie Pirates of the Caribbean. A clinometer is a useful piece of equipment for measuring angles and calculating approximate heights. It is used frequently in forestry, engineering and astronomy. It was invented over 1,000 years ago and was an important piece of equipment for early navigators. You can use it here today to estimate the height of our classroom wall! Let’s make a Clinometer! 1. Cut out the protractor template below and glue it on INDEX paper. 2. Tape the 20 cm string to the flat edge of the protractor, so that the end of the string touches the vertical line in the centre. To make sure it is secure, tape the string to the back of the protractor and wrap it around the bottom. 3. Tie a paperclip to the other end of the string. Let it swing freely. 4. Now, glue a straw to the flat edge of the clinometer. The finished product should look like the figure on the right.
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Mathematics Lesson Plan - EDFE 3200 D November 2, 2017
Protractor Template:
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Mathematics Lesson Plan - EDFE 3200 D November 2, 2017
APPENDIX B Using the Clinometer to Find The Height of our Classroom Wall You can now put your clinometer to use.
Find the angle of elevation by looking through the straw to line up the top of the wall. The string hanging down will show you an angle reading, which you must subtract from 90 degrees to get the angle of elevation. Let’s measure the height of our classroom wall: 1. Work in pairs - one holding the clinometer and the other measuring and recording information. 2. Stand a distance away from the wall and measure the distance between the wall and observer. 3. View the top of the wall using the clinometer through the straw so that the string is vertical. 4. Record the angle reading where the string falls and calculate the angle of elevation. 5. Draw a diagram in the paper/grid provided (Appendix C) and label all your measurements correctly. 6. Now, use the correct trigonometric ratio to measure the approximate height of the wall. (If you were measuring the height of a tree)
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Mathematics Lesson Plan - EDFE 3200 D November 2, 2017
APPENDIX C http://www.projectmaths.ie/documents/T&L/IntroductionToTrigonometry.pdf
Using Trigonometry to Calculate the Height of the Classroom Wall With your partner, record your observations in the chart provided. Height from ground to observer’s eye
Distance between observer and wall
Angle of elevation to the top of the wall
Draw a diagram of the scenario in the space below. In your diagram mark the right angle, the angle of elevation, the hypotenuse, and the adjacent and opposite side with respect to the angle of elevation. Make sure all sides are labelled and measurements are included.
Now it is time to calculate the height of the wall. Look back to your diagram. What are your givens? What side length are you trying to find? What trigonometric ratio uses these two sides?
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Mathematics Lesson Plan - EDFE 3200 D November 2, 2017
APPENDIX D Assessment AS Checklist (used during group activities) Learning Goal: We are learning to measure the height of an object using tangent ratio.
Success Criteria: 1. I made the clinometer following instructions. 2. I measured the angle of elevation using the appropriate technique. 3. I measured all distances needed for solving the problem correctly.
Student Name
Discussed Angles
Discussed Data Collection
Discussed Trig Ratios
Drew a diagram to represent the scenario
Other Notes
I – student initiated the discussion E – student expanded on the topic discussed O – student observed the discussion and seemed engaged, without necessarily adding to it 9