Be Precise Teacher Materials

Transcription

1 Be Precise Teacher Materials TC-1: The lesson should begin with a discussion about why precision in measurement is important. Ask students what things in their life have to be measured accurately. Expand the conversation with ideas about real-life examples such as building houses and why measurement is important, surgery and what would happen if a surgeon was off on the measurements, the Hubble Telescope and what happened when the measurements were off when the main mirror was being ground to transmit photos, etc. Use Student Activity-1 - Measure Up as the introductory activity. The pre-assessment provides a quick check of a student s ability to recognize and label standard units of measure. The activity could be used as a class activity and corrected together to see immediate results or collected to be corrected by the teacher. The pre-test would be helpful for students to keep during their work on the following lessons. Since the focus is to pre-assess, the activity will identify the students who do not have the measurement skills as determined by 7 th grade GLE s. This determination can help teachers form small groups to work with for remediation and modification. Student Activity-1 - Measure Up This helps the teacher assess the students knowledge of measurement tools and how accurately the student can measure/draw a line. Be sure to specify units: whole inches, half inches, 1/8 inch. Make sure everyone can draw lines of given measure to 1/8-inch accuracy. Some students may need additional practice with this. A small group lesson would be helpful for this remediation. TC-2: This activity could serve as a modification for students who are not able to measure and draw accurately on Student Activity 1 or as a way to have students practice the use of precise marking of units of measure. Copy the ruler template on cardstock, if possible, to provide a ruler to be used in future activities. Students will mark and label with precision the units of measure most appropriate for their level of work. Suggested units would be to use 1/16 of an inch. This would best be demonstrated on the overhead to provide students with an exact model of how to mark their ruler. Discussion could center on why 1/8 or 1/16 is a useful increment to use. Students could also look at ready made measuring tools to see what increments are used most often. The six lines on the bottom of the handout (Student Activity 2- How Precise Can You Be?) provide more practice and/or simplification of the actual measuring of objects. This could be done as a warm-up activity or homework for students to use with their ruler produced in the first part of the activity. Be Precise Teaching Materials Page 1 of 14

2 TC-3: Student Activity 3 is intended as a warm-up activity. Students should first list the unit they would choose to measure each object. Use an overhead transparency to discuss this as a class. Ask questions about precision of measure and emphasize tools that may be used to achieve the desired precision. Some objects may be measured in more than one unit and with more than one tool. This could lead to discussion about when and why we need to be precise. Have students explain their choices and justify using mathematical terms and vocabulary TC-4: Use Student Activity 4. The purpose of this activity is for students to select the proper measuring tool for the objects being measured and to decide what makes a precise measurement. Discussion should center on which unit is appropriate for the item being measured and what level of precision is needed. For this activity it is important to identify the standard units of measure that will be used. Direct instruction may be needed to clarify the units being used including: 12 inches=1 foot, 3 feet = 1 yard, 36 inches = 1 yard, etc. During this discussion it would be useful to ask a few questions about how different units are used in everyday life. The previous activities which are lower grade level than grade 7, can be used to review/reinforce the basic standard units. Students will select the tool and measure the object as a class activity. This could be done at stations in the classroom or with partners. The goal is to have student measure the object to the most precise unit possible with the tool they are using. Student Activity 3 may be helpful as a pre-activity to discuss different units and how they can be used to determine precise measures. This could be done as a whole class or individual/small group activity. Students could use string to measure their hands, arms, etc., and then use rulers to measure the string. A partner would be needed to measure their height. After completing the activities, discussion should focus on justifying tools used to get a precise measurement. Students should use appropriate vocabulary when explaining their choice. The questions about perimeter and area move students from standard units being measured to square units. Questions should focus on the differences between measures of length and perimeter to measures of square units. Include vocabulary review about the difference between units and square units. This may be used as a direct teaching activity or be a challenge to higher-level learners. It could also be done as a whole class activity using an overhead transparency and teaching the activity directly. Be Precise Teaching Materials Page 2 of 14

3 TC-5: This activity requires a trip to the school gym. (The activity could be integrated into a P.E. class if appropriate.) Students will use their work from Student Activity 4 to convert measurements. It will be helpful to discuss the rules of basketball before doing this activity. This would provide an opportunity for some students to tell about their participation in sports. It may also be useful to have the rules of the game as well as the size of the court on hand to discuss before doing the measurements. The class should agree on what part of the key they will be measuring for the activity. Teacher questions should focus on why different units of precision are appropriate in different situations. As an opening activity, discussion should focus on the length of hands, arm length and feet. (Be sensitive to individual students.) This provides an opportunity to discuss relationships between arm length and height and could lead to extension activities on ratios. Students will also have the opportunity to think about reallife situations involving sports and connections to height. To wrap up these activities, the students will use standard measures of length. The first part of the activity is to demonstrate their knowledge of standard units of measure and fill in values. Students have been using these measurements for previous activities and the basic units have been discussed. Use Student Activity 5. TC-6: The final activity for this lesson is Student Activity 6-Can You Convert? This could be used as an extension or a culminating activity. The activity sheet has students adding and subtracting measurements involving units that need to be renamed in the answer. The last section of the activity has students combine estimating skills and converting measures to appropriate units. The students will demonstrate their computation skills and their understanding of converting units of measure. Again, this could be extended to more of a challenge for some learners or used with the whole class as a direct teaching activity. Questioning for students could center on common units used in real life and situations where students may use this type of conversions. Be Precise Teaching Materials Page 3 of 14

4 1: Blackline Master #1 This pre-assessment provides a quick check of a student s ability to recognize and label standard units of measure. The activity could be used as a class activity and corrected together to see immediate results or collected to be corrected by the teacher. The pretest would be helpful for students to keep during their work on the following lessons. Student Activity 1 KEY Name Measure Up Label each ruler with the correct measurements. The rulers are in inches. Use a ruler and draw a line that is: /4 inches /8 inches Be Precise Teaching Materials Page 4 of 14

5 Student Activity 2 Key Use a standard ruler and label to the nearest 1/16 th of an inch for the first inch and to the nearest 1/8 th of an inch for the rest of the ruler. Cut out to use. Student Activity 2 Key Name How Precise Can You Be? Use your ruler to measure each line to the nearest 1/8 th of an inch. Graphics will be added. 1. 4/8 or ½ inch /8 inches /8 or 2 ¼ inches 4. 3 ½ or 3 4/8 inches /8 inches /8 or 2 ¾ inches Be Precise Teaching Materials Page 5 of 14

6 Student Activity 3 Key Name Which Unit? Using Precise Measurements Think about what tool you would use to measure each object. Choose the correct unit to measure each object: Inch, Foot, Yard, Mile Be Precise Teaching Materials Page 6 of 14

7 Student Activity 4 Key Name Before you begin Decide which tool to use Decide on the unit of measure to use Estimate each measurement Precision Measurement Item Measuring Tool Unit of Measure Estimate Actual Measurement E- M Length of pinkie finger Length of hand Arm to elbow Foot Height Thickness of math book Length of pen Length of desk Width of desk Height of door Width of door Your choice Your choice Your choice Be Precise Teaching Materials Page 7 of 14

8 1. If you could only use one tool to measure these objects, which tool would you use? Explain why you would use that tool. 2. Look at the last column of the table. Were most of your estimates less than the actual measure or greater than the actual measure? Explain why you got that result? How could you refine your estimate? 3. Record your measurements for the desk and the door. Desk/Table Length Door Length Width Width Use the measurements to find the perimeter of each object. Perimeter of desk= Perimeter of door= Label each answer with the correct units. Why is this unit the most appropriate for this type of measurement? Now find the area of the desk and the door. Area of desk= Area of door= Label each answer. Explain what the differences are between an object s perimeter and its area. Be specific. Be Precise Teaching Materials Page 8 of 14

9 Discuss the E-M section which means estimate-measure. Answers for this activity will vary. Students should see that their estimates vary and they may notice they get more accurate with more practice. Discussion should take place to emphasize the use of proper tools for measuring different lengths and widths. Students should have an understanding of perimeter and area and should be applying this skill in the questions they answer Be Precise Teaching Materials Page 9 of 14

10 Student Activity 5 Key Name Basketball Counts-Converting Measurements What makes height so important in basketball? Is it the only thing that matters? Is precision in measurement important in sports? Try this activity. Use the measurements from Student Activity 4. Convert your measurements to the correct units. You may need to re-measure some of your objects for precision. 1. What was the measure of the length of your hand to the nearest ¼ inch? To the nearest 1/8 inch? 2. Using the measurement of your height in inches, convert it to feet and inches. feet inches Explain how you found the answer using words or showing your steps. 3. List the heights of five people in your class using measurements to the nearest ½ inch. Name Height to nearest ½ inch Be Precise Teaching Materials Page 10 of 14

11 This is going to be your class basketball team. What is the average height of your team to the nearest ½ inch? Explain how you found the average. 4. Explain why a coach would want to use precise measurements to determine the height of his players. 5. What other qualities would you want on your team other than tall players? 6. Go to the school gym. Measure the length of the free-throw line from the end of the court to the line where you stand to shoot.. Measure the width of the free-throw line from one side of the key to the other. What is the most precise way to measure the perimeter of the free-throw region? Perimeter= Label the units. 7. Measure the perimeter of the basketball court. Make a sketch of the court and label the dimensions. Be sure to use correct units. Length Width Total Perimeter Be Precise Teaching Materials Page 11 of 14

12 What is the area of the basketball court? What unit is the best for this measurement? Explain why you selected this unit. 8. Give examples of something in your school gym or around the school that can be measured in each of the units listed and explain why that is the appropriate unit to use. Inches: (object) Explain unit Feet: (object) Explain unit Yards: Explain unit Miles: Explain unit: 9. Describe why precision in measurement is important. Answers will vary. Students should notice that the precision of their measurement can be affected by the tool they use and their purpose for measuring an object. A regulation basketball court in international games is 28 by 15 meters (approx. 92 by 49 ft) and in the NBA is 94 by 50 feet (29 by 15 m). Be Precise Teaching Materials Page 12 of 14

13 Student Activity 6 Key Name Can You Convert?? Units of measure need to be precise to be useful in everyday situations and solving problems. Complete the following conversions. Use your ruler, a 12 ruler or a yard stick as needed. 12 inches = 1 foot 6 ft 4 in = 76 inches 3 feet = 1 yard 2 yds 2 ft = 96 inches 1 yard = 36 inches 28 in = 2 feet 4 inches 3 ½ feet = 42 inches 1 mile = 5280 feet 3 ½ feet = 1 yd. 6 in.yards 1 mile = 1760 yards 4 ft 9 inches 5 yds 2 ft 9 ft 3 inches + 5 ft 6 inches +3 yds 1 ft -4 ft 8 inches 10 ft 3 inches 8yds 3 ft=9yds 4 ft 7 inches over Be Precise Teaching Materials Page 13 of 14

14 Look around the classroom. Find an object that is approximately the given length. Answer the questions below. Approximate Measurement Object Another unit of Measure 14 inches 1 foot 2 inches 22 inches 1 foot 10 inches 4 feet 1 yard 1 foot/48 inches 6 feet 2 yards/72 inches Challenge: Answers will vary Perimeter of 20 feet Whiteboard 4x6 size 240 inches Area of 24 square feet Table 6x4 size 24 sq. feet/2 2/3 sq. yds Be Precise Teaching Materials Page 14 of 14