Measurement of Length a (Guided Activity)

Home , Centimetre, Decimetre, Kilometre, Millimetre

CHAPTER 5 Measurement of Length A (Guided Activity)

Assessment for Feedback What You Will See Students Doing . . . Students will When Students Understand If Students Misunderstand • measure the length of an object, • Students will accurately select an appropriate unit of • Some students may have difficulty converting between units of using the International System measurement, measure the length of an object, and convert measurement. Make certain these students understand the chart of Units (SI) and convert between units of measurement. at the beginning of this lesson and give students extra guided between units of measurement practice making several conversions.

1. Introduction (Whole Class) ➧ 5–10 min Practising (Independent) 6.–12. Students should complete these questions Discuss with students the different types of measurement, independently. such as length, area, mass, volume, and the fact that there is a different base unit of measurement for each type in the Closing (Whole Class): Ask, “What is the base unit for International System of Units. measuring length in the SI system of measurement? How many centimetres are in one metre? How many metres are in one kilometre? How many millimetres are in one metre? How many decimeters are in one metre? How do you convert from one unit of measurement to another?” 2. Teaching and Learning (Whole Class/Pairs) ➧ 15–20 min Read aloud to the class the information at the beginning of Answers the lesson. Make certain that students become familiar with the prefixes used for each unit of measurement. Use a metre A. 1) decimetre 7) millimetre stick to give students a visual representation of each unit of measurement. Discuss the conversion chart near the beginning 2) metre 8) centimetre or decimetre of the lesson and the methods for using it to convert from one 3) metre or decimetre 9) millimetre or centimetre unit of measurement to another. Direct students’ attention to prompt A. Guide them through prompts A and B. Ask 4) centimetre 10) centimetre students to work in pairs to complete prompts C through E. 5) millimetre 11) millimetre When all pairs have had an opportunity to complete all six prompts, discuss answers together as a class. 6) metre 12) centimetre or millimetre Reflecting: Use these questions to ensure that students are able to measure the length of an object, using the SI system of measurement and convert between units of measurement. Sample Discourse: 1. • metre 2. • kilometres-distance between two cities millimetres—width of a thimble

3. • 100 000

3. Consolidation ➧ 20–30 min Checking (Whole Class) 4.–5. Ask students to complete these questions independently. After all students have had an opportunity to complete both questions, check their answers together as a class.

Copyright © 2009 by Nelson Education Ltd. 5A Measurement of Length 1 B. & C. 1.–3. See sample answers under Reflecting. Estimate 4. a) metre c) metre e) millimetre (Answers Actual b) kilometre d) decimetre f) centimetre Object will vary.) Measurement 5. a) 5 c) 14 000 e) 2000 b) 800 d) 2 f)9 1. student desk 5 dm (Answers will vary.) 6. a) millimetre d) centimetre or decimetre b) kilometre e) centimetre or decimetre 2. front classroom wall 7 m c) metre f) millimetre 3. teacher’s desk 2 m 7. a) 70 c) 26 000 e) 25 000 4. ink pen 12 cm b) 360 000 d) 2440 f) 2.58 5. width of a pencil 8. 30 mm eraser 6 mm 9. a) 6. chalkboard 6 m b) 7. width of a piece of chalk 9 mm c) 8. piece of writing paper 16 cm d) 9. small paper clip 18 mm e) 10. stapler 10 cm f) 11. staple 11 mm 12. chalk eraser 12 cm 10. a) 2 km c) 200 cm e) 1 m b) 1 m d) 1 dm f)2000 m D. Kilometres should only be used for long distances. Metres 11. a) 2 km c) 4 km e) 8 dm can be used for anything larger than a metre. If a metre is b) 40 cm d) 30 000 mm f)9 mm too large, students should have used a decimetre. If a decimetre is still too large centimetres can be used. If an 12. a) no b) yes c) no d) no e) yes f)no object is extremely small, then a millimetre is the most appropriate unit of measurement. E. Answers will vary. Students should state if their estimates were close to the actual measurement. If estimates were not close, they should give a specific reason for the difference.