28
Assessing students’ Assessing students’ understanding of understanding of parallel lines and related parallel lines and related angle properties in a angle properties in a dynamic geometry dynamic geometry environment environment CHENG, Lo Carol CHENG, Lo Carol True Light Middle School of Hong True Light Middle School of Hong Kong Kong

Assessing students’ understanding of parallel lines and related angle properties in a dynamic geometry environment CHENG, Lo Carol True Light Middle School

Embed Size (px)

Citation preview

Assessing students’ Assessing students’ understanding ofunderstanding ofparallel lines and related angle parallel lines and related angle properties in a dynamic properties in a dynamic geometry environmentgeometry environment

CHENG, Lo CarolCHENG, Lo Carol

True Light Middle School of Hong KongTrue Light Middle School of Hong Kong

Assessment in mathematics education Assessment in mathematics education

should not just focus on rote memorization should not just focus on rote memorization of number facts or ability for computational of number facts or ability for computational procedures but students’ thinking and procedures but students’ thinking and learning potential in mathematics learning potential in mathematics

mathematics education should help mathematics education should help students to think mathematically and train students to think mathematically and train up their mathematical thinking. up their mathematical thinking.

Ginsburg, H. P., Jacobs S. F. & Lopez L. S. (1993). Assessing mathematical thinking and learning potential in primary grade children In M. Niss (Ed.), Investigations into assessment in mathematics education: An ICMI study (pp. 157–167). Dordrecht: Kluwer Academic Publishers.

Technologies shifts assessment formatTechnologies shifts assessment format

For example: use of calculatorFor example: use of calculator

Dynamic Geometry as Assessment ToolsDynamic Geometry as Assessment Tools

DG software:DG software: SketchpadSketchpad GeoGebraGeoGebra C.a.R.C.a.R.

Use of DG: Use of DG: ExplorationExploration ConstructionConstruction

Can we use DG as assessment tool?

DG Task example

What can we tell from the assessment?

Learning and Teaching of GeometryLearning and Teaching of Geometry

Perceptual ApprehensionPerceptual Apprehension It is about physical recognition (shape, It is about physical recognition (shape,

representation, size, brightness, etc.) of a representation, size, brightness, etc.) of a perceived figure. perceived figure.

Duval, R. (1995). Geometrical pictures: Kinds of representation and specific processings. In R. Sutherland & J. Mason (Eds.), Exploiting Mental Imagery with Computers in Mathematics Education (pp. 143–157), Springer published in cooperation with NATO Scientific Affairs Division.

Learning and Teaching of GeometryLearning and Teaching of Geometry

Sequential ApprehensionSequential Apprehension It is about construction of a figure or It is about construction of a figure or

description of its construction. description of its construction.

Duval, R. (1995). Geometrical pictures: Kinds of representation and specific processings. In R. Sutherland & J. Mason (Eds.), Exploiting Mental Imagery with Computers in Mathematics Education (pp. 143–157), Springer published in cooperation with NATO Scientific Affairs Division.

Learning and Teaching of GeometryLearning and Teaching of Geometry

Discursive ApprehensionDiscursive Apprehension Mathematical properties represented in a Mathematical properties represented in a

drawing can only be clearly defined with drawing can only be clearly defined with speech determination. speech determination.

Duval, R. (1995). Geometrical pictures: Kinds of representation and specific processings. In R. Sutherland & J. Mason (Eds.), Exploiting Mental Imagery with Computers in Mathematics Education (pp. 143–157), Springer published in cooperation with NATO Scientific Affairs Division.

Learning and Teaching of GeometryLearning and Teaching of Geometry

Operative ApprehensionOperative Apprehension It is about making modification of a given figurIt is about making modification of a given figur

e in various ways:e in various ways: the mereological way: dividing the whole given figuthe mereological way: dividing the whole given figu

re into parts of various shapes and combine these re into parts of various shapes and combine these parts in another figure or sub-figures;parts in another figure or sub-figures;

the optic way: varying the size of the figures;the optic way: varying the size of the figures; the place way: varying the position or its orientatiothe place way: varying the position or its orientatio

n.n.Duval, R. (1995). Geometrical pictures: Kinds of representation and specific processings. In R. Sutherland & J. Mason (Eds.), Exploiting Mental Imagery with Computers in Mathematics Education (pp. 143–157), Springer published in cooperation with NATO Scientific Affairs Division.

Dynamic Geometry Tasks Dynamic Geometry Tasks related to parallel linesrelated to parallel lines

Tasks for orientation preferenceTasks for orientation preference

Task 2aTask 2a

Students’ answersStudents’ answers

More than 70 students considered just the horizontal pair.

10

20

30

40

50

60

70

80

80 85 90 95 100 105 110 115 120

var3

Collection 1 Histogram

-2 0 2 4 6 8

Collection 1 Scatter Plot

About 50 students considered both pairs

10

20

30

40

50

60

70

80

80 85 90 95 100 105 110 115 120

var3

10

20

30

40

50

60

70

80

90

80 85 90 95 100 105 110 115 120

var4

About 20 students considered just the vertical pair.

10

20

30

40

50

60

70

80

90

80 85 90 95 100 105 110 115 120

var4

0

1

2

3

4

5

6

Tasks for orientation preferenceTasks for orientation preference

Task 2bTask 2b

Students’ answersStudents’ answers

About 50 students considered just the horizontal (interior angles) pair.

10

20

30

40

50

60

82 84 86 88 90 92 94 96 98 100

var4

Collection 1 Histogram

Collection 1 Scatter Plot

10

20

30

40

50

60

82 84 86 88 90 92 94 96 98 100

var3

Collection 1 Histogram

About 40 students considered just the vertical (corr. angles) pair.

About 40 students considered both pairs.

10

20

30

40

50

60

82 84 86 88 90 92 94 96 98 100

var3

Collection 1 Histogram

10

20

30

40

50

60

82 84 86 88 90 92 94 96 98 100

var4

Collection 1 Histogram

Task for angle positionTask for angle position

Task 3aTask 3a

Students’ answersStudents’ answers

More than 100 students got the correct answers 69 but still there are more than 30 made the angle 62

20

40

60

80

100

var3

56 58 60 62 64 66 68 70 72 74

Collection 1 Histogram

Task for angle positionTask for angle position

Task 3bTask 3b

Students’ answersStudents’ answers

10

20

30

40

50

var3

102 104 106 108 110 112 114 116 118 120

Collection 1 Histogram

More than 80 students the angle as 116 (i.e. 94 + 116 = 180). About 60 students got the values ranged form 111 to 113

Tasks for making equal areasTasks for making equal areas

Task 5aTask 5a

Students’ answersStudents’ answers

20

40

60

80

100

var4

22 24 26 28 30

Collection 1 Histogram

5

10

15

20

25

30

35

40

var3

22 24 26 28 30

Collection 1 Histogram

More than 50 students made all the angles equal 26.

20

40

60

80

100

var4

22 24 26 28 30

Collection 1 Histogram

5

10

15

20

25

30

35

40

var3

22 24 26 28 30

Collection 1 Histogram

About 50 students tried to make a parallelogram.

Tasks for making equal areasTasks for making equal areas

Task 5bTask 5b

Students’ answersStudents’ answers

10

20

30

40

50

60

70

80

var5

22 24 26 28 30 32 34 36 38 40

Collection 1 Histogram

10

20

30

40

50

60

70

80

var6

22 24 26 28 30 32 34 36 38 40

Collection 1 Histogram

5

10

15

20

25

30

35

40

var4

52 54 56 58 60 62 64 66 68 70

Collection 1 Histogram

5

10

15

20

25

30

35

40

var7

52 54 56 58 60 62 64 66 68 70

Collection 1 Histogram

More than 70 students gave correct answers but many of them tried to make a rhombus-like figure.

0

1

2

3

4

5

0 2 4 6 8

var1

Collection 1 Scatter Plot

10

20

30

40

50

60

70

80

22 24 26 28 30 32 34 36 38 40

var5

Collection 1 Histogram

More than 100 students made a rhombus-like figure.