Mathematics in Indigenous Contexts

Gilgandra 2005

Artist: Errol Roberts

Artworks: Culcha Disc, Australian Indigenous Images Volume 1

Available from Keeaira Press www.kpress.com.au

Unit Outcomes

Number

NS3.2

Selecta and applies appropriate strategies for addition and subtraction with counting numbers

of any size

NS3.3

Selects and applies appropriate strategies for multiplication and division

NS4.1

Recognises the properties of special groups of whole numbers and applies a range of

strategies to aid computation

NS4.3

Operates with fractions, decimals, percentages, ratios and rates.

Measurement

MS3.1

Selects and uses the appropriate unit and devices to measures lengths, distances and

perimeters

MS4.1

Uses formulae and Pythagoras’ theorem in calculating perimeter and area of circles and figures

composed of rectangles and triangles.

Space and Geometry

SGS2.2 (a)

Manipulates, compares, sketches and names two-dimensional shapes and describes their features

Working Mathematically

WMS3.1

Asks questions that could be explored using mathematics in relation to Stage 3 content

WMS3.2

Selecta and applies appropriate problem solving strategies including technological

applications in undertaking investigations

WMS4.2

Analyses mathematical or real life situations, solving problems using technology where appropriate

Units of Measure

MS3.1, WMS3.2, MWS4.2

Discussion Questions

1. Why do we need to have standard units of measure?

______

______

______

2. List 4 jobs where measurement is used and very important.

______

______

3. What unit of measure would YOU use to measure the following:

a) Your height ______

b) The length of a car ______

c) The length of a matchstick ______

d) The distance you travel to school ______

e) The length of a train ______

f) The length of a new born baby ______

Smallest mm millimetres

cm centimeter

s

m metres

km kilometre

Largest

Relationship between units

10 mm = 1 cm

100 cm = 1 m

1000 m = 1 km

A very Special Relationship: In the building industry

1000 mm = 1 m

km x 1000 m x 100 cm x10 mm

mm ¸10 cm ¸ 100 m ¸1000 km

MS3.1, WMS3.2, Reasoning

Outcome: To be able to draw intervals of a given length without a ruler

To improve my ability to estimate

Equipment Needed: Pencil and a straight edge without any markings on it

Exercise: Draw intervals of the given length

1. 10 mm

2. 20 mm

3. 5 mm

4. 50 mm

5. 3 cm

6. 10 cm

7. 1 cm

8. 2 cm

9. 3 ½ cm

10. 25 mm

11. 8 mm

12. 42 mm

13. 4.2 cm

14. 12 cm

15 120 mm

Now measure each interval accurately with a ruler writing the exact measurement along side each one

Exercise:

Estimate how long these intervals are:

Question 1 – 6 estimate in milimetres.

1. ______

2. ____

3. ______

4. ______

5. ______

6. ______


Question 7 – 12 estimate in centimetres

7. ____

8. ______

9. ______

10. ______

11. ______

12. ______

NOW MEASURE AND WRITE THE MEASUREMENT ALONGSIDE THE GIVEN INTERVAL

1. How close were you?______

______

2. Which was easiest to estimate: mm or cm?______

Why? ______

MS3.1,WMS3.2/4.2.ReasoningProcess

SNAKES

v  Students makes ‘snakes’ using playdough

v  Students estimate, measure, and label the length

written in a different form, eg 20 cm , 0.2 m …

v  Order their snakes in terms of length and note the different

ways to record the same length

v  Could you estimate, measure and record the length of your snake

v  Did your recognize the length of your snake recorded

using a different unit of measure?

Record your measurement using decimal

notation to two decimal places?

Convert your measurement to

i) millimetres ______

ii) centimetres ______

MS3.1,WMS3.2/4.2

MEASUREMENT – SMALL OBJECTS

Investigation Exercise

Estimate and measure the length or width of a selection of small

objects to the nearest millimetre and record the results in the table

using millimetres and a combination of millimetres and centimetres

Estimate / Measurement in mm / Measurement in cm and mm
Width of pencil
Length of a pencil
Sharpener
Length of a paper clip
Thumb Nail
Stick of chalk
Pen lid
Watch Band

1. Which unit of measure was the best to use?

Why?

2. Which is was the more accurate mm or cm ? Why?

MS3.1,WMS3.2/4.2,Reasoning Process

APPROPRIATE MEASURE

PROBLEM

1. Jacob needs to measure the length of his eraser.

What measuring device and unit of measure do you suggest

be best for him to use? ______

______

______

2. He now needs to measure the length of his desk, the room and

the playground.

What measuring device and unit of measurement would you suggest

he uses? ______

______

______

______

3. Measure these things and record your answer in the table.

Measurement
Length of desk
Length of room
Length of playground

INVESTIGATION

You are to locate (find), measure and records the lengths of THREE

objects of which one is

i) smaller than 1cm

ii) bigger than 1 cm

iii) bigger than 10 cm and smaller than 1 m


Place the name of the object you selected and write the measurement

in the different units.

Measurement / In Metres / In Centimetres / In Millimetres
Watch Band Width / 0.018 / 1.8 cm / 18mm

What measuring device did you use? ______

Why did you select this device? ______

______

______

What unit did you use to record your measurements initially?

______

______

How did you convert your measurements to

a) millimetres

b) centimetres

c) metres?

MS3.1,NS3.2,NS4.1,NS4.3

MY PERSONAL PROFILE

Name ………………………..

Age ……………………………

Estimate / Actual / Difference
Height
Hand Span
Elbow to the tip of middle finger
Arm Length
Arm Span (both)
Foot Length (right)
Foot Length ( Left)
Length of Thumb
Distance Around Head
Pace

Key Points Used in Planning/Writing Units

v  How well do we expect the students to do the tasks we set?

v  What do we want the students to learn?

v  Why does it matter

v  What are we going to get the students to actually do?

v  When will they need to know this and why?

Suggested Outcomes

v  Selects and uses the appropriate unit and device to measure lengths

v  Estimates, measures, compares and records lengths, distances in centimetres an millimeters

v  Converts between units of measures

v  Describes the limits of accuracy of measuring instruments

MS3.1,NS4.1,NS3.2,NS4.3,WMS3.2/4.2,SG2.2

Boomerang Activity

Given the outline of a boomerang and a selection of strings

of various lengths- some loose , some in packets rolled up

examine the boomerang-

select from the loose strings which one would around it

select from those in packets which one would around it

measure the distance around the boomerang

compare the actual with the ones you have chosen

which was the easiest – the loose string /or the one in packet

why/why not

THE BOOMERANG

Investigation Activity

1. You are to study the outline of the boomerang on the given sheet of paper

2. Estimate the distance around it , and complete the sentence ;

I estimated the distance around it to be ______

( You have to decide what units of measure you use)

3. Now examine the loose pieces of string. Without actually measuring

determine which piece would go around it.

I have chosen the piece labelled ______

4. Now carefully examine the pieces of string enclosed in the plastic bags.

Choose which bag contains the piece of string you think will go around

the boomerang.

I have chosen bag labelled ______

5. Carefully measure around the boomerang to determine the actual

distance around it.

The actual distance around it is ______mm

______cm

RESULTS

How close in length was your chosen piece of string to the actual

distance around the boomerang

______

What was the difference in these two measurements?______

How close was the string in the bag to the actual distance.

______

What was the difference in these two measurements?______

Which was the easiest to use to estimate: the loose string or the

one in the bag?______

Why______

______

Has your ability to estimate improved since starting this unit of work?

______

6. You are to do a SYMMETRICAL design on the boomerang

and colour it in.



MS3.1,MS4.1,NS3.3,WMS3.1/4.2

TYRES

Investigation and Discovery

1. Use a piece of string (or something similar) and measure

the circumference of a bike or car wheel. Circumference is

the distance around the outside.

Estimate the distance around the tyre ______cm

______mm

______m

2. Measure the string to determine the distance travelled in

in one revolution ( one turn)

Record the measurement in mm ______

cm ______

m ______

3. Calculate the distance travelled in

5 revolutions ______

1000 revolutions______


MS3.1,NS3.2,NS4.1,NS4.3,WMS3.2/4.2

How far does a Bullroarer travel?

(Circumference of a Circle)

Let’s guess how far different BIG bullroarers would travel, if the length of cord was different numbers of steps. How many steps around the circle would the bullroarer travel?

1 One person will stay in the centre standing still and holds the end of the string. The walker stands beside the centre person, and then takes 4 paces, letting out the string.

If the walker keeps walking forward hanging onto the string, what path will they make?

2 How many paces do you think the walker will take around the circle with radius 4 steps?

(Write your guess in the table below)

3 Now count the steps to complete a circle and write in the actual number of Steps.

4 Next write in your guess for a radius of 7 steps and then find its circumference and continue for the rest.

Let’s go back to the room!

5 Divide yours steps by the radius for each one correct to 1 decimal place.

Radius / 4 / 7 / 6 / 10 / 8
My Guess
Steps
Steps¸Radius

6 Describe a relationship between the distance around the circle, and the radius?

(If it exists)

7 Does the relationship work with other members of your group? ______

8 Distance around a circle = x

(circumference)


How far does a Bullroarer travel? Extension Worksheet

(Circumference of a Circle)

The distance around the circle is one of the following, guess now then do the activity.

A Just less than 6 times the radius.

B Exactly 6 times the radius.

C Slightly more than 6 times the radius.

The following activities may help you to decide.

1 Which radius would better help you decide?

If you repeated the walking activity, which radius,

a 2-pace radius, or 10 pace radius would better help?

2 Do the circle-walking activity using heel-to-toe paces

Be as accurate as possible, don’t let the centre move, and Keep the string tight

Radius
Circumference
6 x radius

3 Try using a trundle wheel

Tie one end of the string to a stake in the centre and the other to the handle of the trundle wheel, near the axle. Enter your measurements in the table above.

Conclusion: The distance around a circle is times the radius.

Pre-Test

Name …………………

1. What do these abbreviations stand for:

a) m ______

b) mm ______

c) cm ______

d) km ______

2. Circle which is the largest measure in the following

a) 12 mm or 2 cm

b) 1m or 120 cm

c) 300cm or 3.1 m

d) 3cm or 37 mm

3. Estimate the length of the following objects:

a) the height of the door ______

b) the height of your teacher ______

c) the width of the blackboard ______

d) the length of the piece of chalk ______

d) the width of the watch band ______

4. Complete the following

a) 2 cm = _____ mm

b) 3 m = _____ cm

c) 30 mm = _____ cm

5. Measure the following lines in millimetres

a) ______

b) ______

c) ______

d) _____

6. Draw intervals, given there length in centimetres

a) 4cm

b) 6 cm

c) 3.5 cm

d) 5.2 cm

Post Test

Name

1. What do these abbreviations stand for:

a) cm ______

b) m ______

c) mm ______

d) km ______

2. Which of the following measuring instruments :

ruler, tape measure, trundle wheel, dressmaker’s tape

would you select to measure the following:

a) your height ______

b) the distance around your desk ______

c) the distance (circumference) around your head ______

d) the perimeter of the school ______

e) the length of a piece of chalk ______

f) the length of your classroom ______

d) the thickness of a DVD ______

3. For each of the following circle which is the largest reading:

a) 90 mm or 9.1 cm

b) 250 cm or 2 m

c) 3.25 m or 330 cm

d) 2 cm or 18 mm

e) 2000m or 1.8 km

4. Complete the following conversions:

a) 20 mm = ______cm

b) 3 cm = ______mm

c) 2 m = ______cm

d) 1 m = ______mm

e) 25 mm = ______cm

f) 500 cm = ______m

g) 2.5 cm = ______mm

h) 300 mm = ______cm

i) 75 cm = ______m

j) 0.3 m = ______cm

5. Using the appropriate equipment draw intervals the following

lengths

a) 5 cm

b) 80 mm

c) 8 ½ cm

d) 38 mm

e) 58 mm

f) 7.5 cm

6. In each of the following sets of measures, circle the measurements

that are equal.

a) 300 cm , 30 m, 3 m , 3000 mm

b) 25 mm, 25 m, 2.5 cm, 25 cm

7. Using your measuring equipment , measure the sides of the following