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Table of Contents Table of Contents Teaching and Learning The Metric System Unit 1 1 - Suggested Teaching Sequence 1 - Objectives 1 - Rules of Notation 1 - Metric Units, Symbols, and Referents 2 - Metric Prefixes 2 - Linear Measurement Activities 3 - Area Measurement Activities 5 - Volume Measurement Activities 7 - Mass (Weight) Measurement Activities 9 - Temperature Measurement Activities 11 Unit 2 12 - Objectives 12 - Suggested Teaching Sequence 12 - Metrics in the Office 12 - Type It Metric Style 13 - Write & Spell It Right 16 - Trying Out Metric Units 17 - Use Those Metric Terms 18 - Writing Metric Terms 19 Unit 3 20 - Objective 20 - Suggested Teaching Sequence 20 - Metric-Metric Equivalents 20 - Changing Units at Work 22 Unit 4 23 - Objective 23 - Suggested Teaching Sequence 23 - Working With Metrics 23 - Proofreading Metric Terms 24 - Metric Layouts 25 Unit 5 26 - Objective 26 - Suggested Teaching Sequence 26 - Metric-Customary Equivalents 26 - Any Way You Want It 27 Testing Metric Abilities 28 Answers to Exercises and Test 29 Tools and Devices List References TEACHING AND LEARNING THE METRIC SYSTEM This metric instructional package was designed to meet job-related Unit 2 provides the metric terms which are used in this occupation metric measurement needs of students. To use this package students and gives experience with occupational measurement tasks. should already know the occupational terminology, measurement terms, and tools currently in use. These materials were prepared with Unit 3 focuses on job-related metric equivalents and their relation­ the help of experienced vocational teachers, reviewed by experts, tested ships. in classrooms in different parts of the United States, and revised before distribution. Unit 4 provides experience in recognizing and using metric units, Each of the five units of instruction contains performance objec­ terms, and symbols in proofing, typing, and layout tasks. tives, learning activities, and supporting information in the form of text, exercises, and tables. In addition, suggested teaching techniques are included. At the back of this package are objective-based evaluation Unit 5 is designed to give students practice in converting custom­ items, a page of answers to the exercises and tests, a list of metric ary and metric measurements. Students should learn to "think metric" materials needed for the activities, references, and a list of suppliers. and avoid comparing customary and metric units. However, skill with conversion tables will be useful during the transition to metric in each occupation. Classroom experiences with this instructional package suggest the following teaching-learning strategies: Using These Instructional Materials 1. Let the first experiences be informal to make learning the metric This package was designed to help students learn a core of knowl­ system fun. edge about the metric system which they will use on the job. The exercises facilitate experiences with measurement instruments, tools, 2. Students learn better when metric units are compared to familiar and devices used in this occupation and job-related tasks of estimating objects. Everyone should learn to "think metric." Comparing and measuring. metric units to customary units can be confusing. 3. · Students will learn quickly to estimate and measure in metric units This instructional package also was designed to accommodate a by ·'doing." variety of individual teaching and learning styles. Teachers are encour­ aged to adapt these materials to their own classes. For example, the 4. Students should have experience with measuring activities before information sheets may be given to students for self-study. References getting too much information. may be used as supplemental resources. Exercises may be used in inde­ 5. Move through the units in an order which emphasizes the sim­ pendent study, small groups, or whole-class activities. All of the plicity of the metric system (e.g., length to area to volume). materials can be expanded by the teacher. 6. Teach one concept at a time to avoid overwhelming students with Gloria S Cooper too much material. Joel H. :\lagisos Unit 1 is a general introduction to the metric system of measure­ Editors ment which provides informal, hands-on experiences for the students. Th1s publication was developed pursuant to contract No. OEC-0-74-9335 w1th the This urit enables students to become familiar with the basic metric Bureau of Occupationa l and Adu lt Education. U .S. Department of Health. Educa· units, their symbols, and measurement instruments; and to develop a t ion and Welfare. However, the opini ons expressed herein do not necessarily set of mental references for metric values. The metric system of nota­ reflect the posit iOn or po licy of the U .S. Office of Education and no official tion also is explained. endorsement by the U .S Office of Education should be inferred. 1 UNIT OBJECTIVES The student will demonstrate these skills for the Linear, Area, Volume or Capacity, Mass, and 1 Temperature Exercises, using the metric terms and measurement devices listed here. SUGGESTED TEACHING SEQUENCE EXERCISES SKILLS Linear rue a Volume or Capacity Mass Temperature 1. These introductory exercises may require two or three teaching periods for all five (pp. 3. 4 ) (pp. 5. 6) (pp. 7 . 8) (pp. 9. 10) (p. 11) areas of measurement. 1. Reco gnize and use the millimetre (mm ) square cubic centi- gram (g) de gree Celsius 3 2. Exercises should be followed in the order unit and its symbol for : centimetre metre (cm ) ("c) centimetre (em) (cm2 ) kilogram (kg) given to best show the relationship 2. Select, use, and read the cubic metre between length, area, and volume. appropriate measuring metre (m) square (m3) instruments for : metre 3. Assemble the metric measuring devices (m2 ) litre (I ) (rules, tapes, scales, thermometers, and 3. State or show a physical reference for: millilitre(ml) measuring containers) and oqjects to be measured.* 4. Estimate within 25% heigh t. width, o r the area of capacity o f the mass o f objects the temperature of 4. Set up the equipment at work stations of the actual measure length o f o bjects a gi ven surface containers in grams and kilo- the air or a liquid for use by the whole class or as individu­ grams alized resource activities. 5. Read correctly metre stick, metric measurements a kilogram scale A Celsius thermometer tape measure, and on graduated and a gram scale 5. Have the students estimate, measure, and metric rulers volume measur· record using Exercises 1 through 5. ing devices 6. Present information on notation and make Table 1 available. 7. Follow up with group discussion of RULES OF NOTATION activities. 1. Symbols are not capitalized unless the unit is a proper name (mm not MM). 2. Symbols are not followed by periods (m not m .). 3. Symbols are not followed by an s for plurals (25 g not 25 gs). 4. A space separates the numerals from the unit symbols ( 4 l not 41 ). *Other school departments may have devices which 5. Spaces, not commas, are used t o separate large numbers into groups of three can be used. Metric suppliers are listed in the reference digits ( 45 271 km not 45,271 km). section. 6. A zero precedes the decimal point if the number is less than one (0.52 g not .52 g). 7. Litre and metre can be spelled either with an -re or -er ending. Information Sheet 1 2 METRIC UNITS, SYMBOlS, AND REFERENTS METRIC PREFIXES Quantity Metric Unit Symbol Useful Referents Multiples and Submultiples Prefixes Symbols Length millimetre 6 nun Thickness of dime or paper 1 000 000 = 10 mega (meg' a) M clip wire 3 centimetre em Width of paper clip 1 000 = 10 kilo (k-ilo) k 2 metre m Height of door about 2 m 100 = 10 hecto (hek' to) h kilometre k.m 12-minute walking distance 10 = 10 1 deka (dek'a) da Area square Area of this space Base Unit 1 = 10° centimetre em 2 0.1 = 10-l deci ( des'f) d D 2 0.01 = 10- centi (sen' tl) c square metre m 2 Area of card table top 0.001 = 10- 3 milli (mil'[) m 6 hectare ha Football field including sidelines 0 .000 001 = 10- micro (mi'kro) J1 and end zones Volume and millilitre ml Teaspoon is 5 ml Capacity litre I A little more than 1 quart Table 1-b cubic centimetre em 3 Volume of this container CJJ cubic metre m 3 A little more than a cubic yard Mass milligram mg Apple seed about 10 mg, grain of salt, 1 mg gram g Nickel about 5 g kilogram kg Webster's Collegiate Dictionary metric ton (1 000 kilol[l'arns) t Volkswagen Beetle Table 1-a 3 LINEAR MEASUREMENT ACTIVITIES 3. Choose a partner to stand at your side. Move apart Metre, Centimetre, Millimetre so that you can put one end of a metre stick on your partner's shoulder and the other end on I. THE METRE (m) your shoulder. Look at the space between you. A. DEVELOP A FEELING FOR THE SIZE OF A METRE 1. Pick up one of the metre THAT IS THE WIDTH OF A METRE! sticks and stand it up on the floor. Hold it in place with one hand. Walk around the B. DEVELOP YOUR ABILITY TO ESTIMATE IN IvlETRES stick. Now stand next to the stick. With your other Now you will improve your ability to estimate in metres. hand, touch yourself where Remember where the length and height of a metre was on your the top of the metre stick body. comes on you. For each of the following items: Estimate the size of the items and write your estimate in the THAT IS HOW HIGH A tvlETRE IS! ESTIMATE column. Measure the size with your metre stick and write the answer in the MEASUREMENT column.
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