TOPIC
Time
Strand: Measures
Strand unit: Time
Curriculum Objectives
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Explore international time zones.
Explore the relationship between time, distance and average speed.
Looking back: What the 5th class programme covered
1. The 24-hour clock.
2. Digital and analogue time.
Maths skills used in this topic
1. Integrating and connecting: Make mathematical connections within mathematics itself,
throughout other subjects, and in applications of mathematics in practical everyday contexts.
2. Understanding and recalling: Understand and recall facts, definitions and formulae.
Concrete materials
Stopwatch
Vocabulary
International time, elapse, local time
Teaching points
1. Some children find average speed difficult to calculate given distance and time. The confusion
may arise from the amount of time quoted:
(a) If the amount of time is less than 1 hour, then we usually multiply to calculate average
speed, e.g. 12km in 13 of an hour. Speed is 3 x 12 = 36kph.
(b) If the amount of time is more than 1 hour, then we usually divide to calculate average
speed, e.g. 12km in 3 hours. Speed is 12 ÷ 3 = 4kph.
2. Discuss the difference between travelling to Europe (clocks go forward)
and travelling to North America (clocks go back). Draw on the children’s
experiences to discuss phoning home, jet lag, etc.
Oral and mental activities
Fans:
How many minutes in 12 hour, 14 hour, 34 of an hour, 2 hours 25 minutes, etc.
Convert and show 100 minutes as hour and minutes. Show 199 minutes, 121
minutes, etc.
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Loop game (see Folens Online resources):
Time
Target board 12:
How many minutes in each number? How many minutes must be added to make another full
hour?
Counting stick:
Count in 12 hours, 14 hours, starting at different whole and mixed numbers.
Topic suggestions
1. ‘Around the World in 80 Days’ – tell the story of the wager Phileas Fogg made. You may recall
that on his return to London he thought he had failed only to discover in the nick of time that
because he had travelled east, he had gained a day. Discuss the International Date Line.
2. When buying airline tickets flight times are always quoted in local time. Even if you buy your
tickets in Ireland for a return flight to New York, the flight times from New York are local.
Discuss why this is a sensible arrangement.
Activity A
1
1. How many minutes in 14 hour, 16 hour, 10
hour? (15 minutes, 10 minutes, 6 minutes)
2. What fraction of an hour is represented by 30 minutes, 45 minutes, 12 minutes? ( 12 hour,
3 hour, 1 hour)
5
4
1
9
3. If 14 hour, 16 hour, 10 hour has elapsed, how much of the hour is left? ( 34 hour, 56 hour, 10
hour)
5
4. If 10 minutes, 12 minutes, 20 minutes ... have gone, what fraction of an hour is left? ( 6
hour, 45 hour, 23 hour)
5. How many minutes in 1 14 hours, 2 hours 25 minutes, 23 hours? (75 minutes, 145 minutes,
40 minutes)
6. Convert 100 minutes, 121 minutes, 199 minutes to hours and minutes. (1 hour 40
minutes, 2 hours 1 minute, 3 hours 19 minutes)
5
7
7. Draw diagrams like those in the book to illustrate 15 of an hour, 10 of an hour and 12 of an
hour.
Differentiation
Lower attainers:
Separate activity sheet
Higher attainers:
1. Separate activity sheet
2. What’s the longest month in the year? (October – the clocks go back in October so the
month is 31 days + 1 hour long)
3. The speed of sound (Mach 1) through air is approximately 333 metres per second (changes
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depending on air temperature) which is equal to approximately 1,200kph. Some aircraft can
fly faster than the speed of sound. Ask the children how long it would take to travel from
Galway to Cork, Dublin to New York, etc. if they could travel at the speed of sound.
4. Speed of light is approximately 300,000 kilometres per second. What distance will light travel
in an hour? (1,080 million km). Name something that travels at a speed close to the speed of
light. (electricity) What is a light year? (distance light travels in 1 year – huge figure: 9,460,800
million km) Who uses light years as units of measurement (astronomers) and why? How long
does it take light from the sun to reach Earth? (8 minutes)
Topic
Topic
1. Calculate your average speed if you travel each of these distances in the times shown.
1. In your head. How far will I travel at these speeds for these times?
E.g. 120km in 10 hours: 120 ÷ 10 = 12. Speed is 12kph.
(a) 2 12 hours at 60kph: ___
(b) 15 minutes at 40kph: ___ (c) 45 minutes at 100kph: ___
(a) 80km in 10 hours: ___
(b) 150km in 10 hours: ___
(c) 230km in 10 hours: ___
(d) 80kph in 12 minutes: ___
(e) 1 12 hours at 50kph: ___
(d) 60km in 12 hours: ___
(e) 75km in 5 hours: ___
(f) 99km in 3 hours: ___
(g) 1 hour and 6 mins at 20kph: ___ (h) 20 mins at 105kph: ___
(g) 72km in 6 hours: ___
(h) 121km in 11 hours: ___
(i) 59km in 1 hour: ___
(j) 150km in 2 hours: ___
(k) 235km in 5 hours: ___
(l) 414km in 9 hours: ___
(a) 150km at 100kph: ___
2. Calculate your average speed if you travel each of these distances in the times shown.
E.g. 60km in 12 hour: 2 x 60 = 120. Speed is 120kph.
(a) 80km in
1
2
hour: ___
(b) 65km in
(d) 40km in
1
4
hour: ___
(e) 8km in
1
4
1
2
hour: ___
(c) 83km in
1
2
hour: ___
(f) 56km in
1
4
hour: ___
hour: ___
(g) 30km in 20 mins: ___
(h) 38km in 20 mins: ___
(i) 84km in 20 mins: ___
(j) 8km in 5 mins: ___
(k) 11km in 5 mins: ___
(l) 16km in 5 mins: ___
(f) 40 minutes at 15kph: ___
(i) 3 12 hours at 115kph: ___
2. How long will it take to travel these distances at these speeds?
(b) 60km at 120kph: ___
(d) 10km at 50kph: ___
(e) 120km at 80kph: ___
(g) 5km at 40kph: ___
(h) 40km at 30kph: ___
(c) 12km at 10kph: ___
(f) 77km at 55kph: ___
(i) 250km at 150kph: ___
3. Tick the correct answer.
(a) Millie set out at 10:45am
(b) A snail covered a distance
(c) If light travels at a speed
and travelled 120km. She
of 120m in 40 minutes.
of 300 thousand km per
arrived at 12:15pm. What
What was its average
second, how far will a beam
(a) Waterford to Galway
(b) Rosslare to Cork
(c) Roscommon to Dublin
was her average speed?
speed?
of light travel in one minute?
(d) Limerick to Kilkenny
(e) Killarney to Athlone
(f) Galway to Rosslare
120kph
4.8kph
18,000km
(g) Dundalk to Dublin
(h) Dublin to Waterford
(i) Donegal to Kilkenny
(j) Cork to Limerick
(k) Athlone to Waterford
(l) Cork to Rosslare
80kph
3kph
180,000km
180kph
0.18kph
1,800,000km
none of these
none of these
none of these
3. Colour the box that shows the distance from the first town to the second.
Dundalk
Galway 238
Kilkenny 172
198
Killarney 198
193
352
Limerick 111
113
105
241
Roscommon 151
264
158
82
151
Rosslare 241
211
275
100
274
246
Waterford 82
208
129
193
48
220
243
Donegal
Dublin 222
85
158
219
204
117
309
309
407
198
296
146
151
163
391
158
357
Athlone
Cork 219
402
183
257
126
325
145
209
93
148
126
87
232
105
121
251
32
208
209
126
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4. At what time should you leave for each of these appointments?
(a) 12:15pm and the journey will take 25 minutes. ___
(b) 3:40pm, the journey will take 45 minutes and you need to stop at a shop for approx.
5 minutes. ___
(c) 4:25pm, the journey will take 35 minutes and you don’t want to be late. ___
(d) 6:45pm, the journey normally takes 55 minutes but there are expected traffic delays of up to
15 minutes. ___
6. A driver travelled from Waterford to Limerick, from Limerick to Galway and from Galway to
Donegal. What was the total distance travelled? _______
Name: _______________________________________
Date: ___________________
Page 153: Time and Speed
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5. (a) Name a country in a time zone that is ahead of our time. __________
(b) Name a country in a time zone that is behind our time. __________
(c) Name a country in the same time zone as ours. __________
(d) For what do the letters GMT stand? __________ Where is Greenwich? __________
(e) How might life be strange if you lived close to a time zone border? __________
Name: _______________________________________
Date: ___________________
© Folens Photocopiables
5. What is the longest distance shown? ___ Which two towns is it between? _______ and _______
© Folens Photocopiables
4. What is the shortest distance shown? ___ Which two towns is it between? _______ and _______
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Page 154: Time and Speed
Linkage
Data: Representing and interpreting data
Integration
PE: Athletics (measuring time, calculating speed, etc.)
SESE Geography: International time zones and why they are necessary, rotation of the Earth from
west to east
Maths at home/parental involvement
Conduct a survey of people at home using questions such as the following: What’s the farthest
distance you have ever been from home? In which time zone was that place? Did you have to
change the time on your watch? If you were travelling to another time zone, which would you
prefer: to put your watch forward 5 hours or to put your watch back 5 hours?
Notes
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