Topicm9679710c290a0938_1528449000663_0Topic

Measuring line segments and polygon chains

Levelm9679710c290a0938_1528449084556_0Level

Second

Core curriculumm9679710c290a0938_1528449076687_0Core curriculum

VII. Lines and line segments. The student:

4) measures the line segmentline segmentline segment with 1 mm accuracy.

XII. Practical calculations. The student:

6) converts and properly uses the units of length: millimeter, centimeter, decimeter, meter, kilometer.

Timingm9679710c290a0938_1528449068082_0Timing

45 minutes

General objectivem9679710c290a0938_1528449523725_0General objective

Using mathematical objects, interpreting mathematical concepts.

Specific objectivesm9679710c290a0938_1528449552113_0Specific objectives

1. Identifying and distinguishing different types of polygon chains.

2. Drawing and measuring line segments and polygon chains of lengths given in centimetres or millimetres.

3. Communicating in English, developing basic mathematical, computer and scientific competences, developing learning skills.

Learning outcomesm9679710c290a0938_1528450430307_0Learning outcomes

The Student:

- identifies and distinguishes different types of polygon chains,

- draws and measures line segments and polygon chains of given lengths in centimetres or millimetres.

Methodsm9679710c290a0938_1528449534267_0Methods

1. Situational analysis.

2. Discussion

Forms of workm9679710c290a0938_1528449514617_0Forms of work

1. Individual work.

2. Group work.

Lesson stages

Introductionm9679710c290a0938_1528450127855_0Introduction

Students share their knowledge about line segments. They give the definition of the line segmentline segmentline segment and examples of its marking. They discuss the ways of measuring the length of the line segment and revise the length units they already know.

Conclusions:

- each line segment has its determined length. We can measure it with using various devices, like the ruler or the tape‑measure,
- the length of the line segments can be expressed in millimetres (mm), centimetres (cm), decimetres (dm).m9679710c290a0938_1527752256679_0- each line segment has its determined length. We can measure it with using various devices, like the ruler or the tape‑measure,
- the length of the line segments can be expressed in millimetres (mm), centimetres (cm), decimetres (dm).

Procedurem9679710c290a0938_1528446435040_0Procedure

Task 1

Students work individually, using computers. Their task is to measure the length of the line segmentline segmentline segment using the ruler presented on the screen.

[Geogebra aplet1]

Task 2

Students draw four different line segments. They measure them with the ruler and determine their lengths in centimetres and millimetres.

Task 3

Students draw line segments of given lengths:

a) 3 cm
b) 1 dm
c) 5 cm and 3 mm

Task 4

Students draw five line segments in such a way that the end of the first one is the beginning of the second, the end of the second one is the beginning of the third, etc. They compare their drawings.

The teacher informs the students that the figure drawn in this way is called a polygon chainpolygon chainpolygon chain.

Conclusions:

- the polygonal chain is a figure made of line segments in such a way that the end of the first line segment is the beginning the second line segment, the end of the second line segment is the beginning of the third line segment, etc. The ends of the line segments are the apexes of the polygonal chain; the line segments are the sides of the polygonal chain,
- the types of the polygon chain: open and closed.m9679710c290a0938_1527752263647_0- the polygonal chain is a figure made of line segments in such a way that the end of the first line segment is the beginning the second line segment, the end of the second line segment is the beginning of the third line segment, etc. The ends of the line segments are the apexes of the polygonal chain; the line segments are the sides of the polygonal chain,
- the types of the polygon chain: open and closed.

[Illustration 1]

[Illustration 2]

Task 5

Students work individually, using computers. Their task is to measure the length of the polygon chainpolygon chainpolygon chain with the ruler presented on the screen.

[Geogebra aplet 2]

Lesson summarym9679710c290a0938_1528450119332_0Lesson summary

Students do the revision exercises. Then together they sum‑up the classes, by formulating the conclusions to memorise.

- each line segmentline segmentline segment has its determined length. We can measure it with using various devices, like the ruler or the tape‑measure,
- the length of the line segments can be expressed in millimetres (mm), centimetres (cm), decimetres (dm),
- the polygonal chain is a figure made of line segments in such a way that the end of the first line segment is the beginning the second line segment, the end of the second line segment is the beginning of the third line segment, etc. The ends of the line segments are the apexes of the polygonal chain; the line segments are the sides of the polygonal chain,
- the types of the polygon chainpolygon chainpolygon chain: open and closed.

Selected words and expressions used in the lesson plan

line segmentline segmentline segment

length of line segmentlength of line segmentlength of line segment

ends of line segmentends of line segmentends of line segment

polygon chainpolygon chainpolygon chain

closed polygon chainclosed polygon chainclosed polygon chain

open polygon chainopen polygon chainopen polygon chain

length of the polygon chainlength of the polygon chainlength of the polygon chain

apexes of the polygon chainapexes of the polygon chainapexes of the polygon chain