Year 4 · Telling the Time and the 24-Hour Clock · Summary

Year 4 Telling the Time and the 24-Hour Clock: summary and key words

Part of the Year 4 telling the time and the 24-hour clock chapter. Chapter overview · whole chapter on one page

Chapter summary

Skill	Method
Analogue clock	Short, thick hand = hours. Long, thin hand = minutes. Each number is 5 minutes. Each small mark is 1 minute.
Past and to	Right-hand side of the clock: minutes past. Left-hand side: take the minutes from 60 and say to the next hour. 7:47 = 13 minutes to 8.
Special times	o’clock (12), quarter past (3), half past (6), quarter to (9).
The hour hand	Use the number it has passed. At 5:55 it is nearly at the 6, but the hour is 5.
Roman numerals	I, II, III, IV, V, VI, VII, VIII, IX, X, XI, XII = 1 to 12. Some clocks use IIII for 4.
12-hour and am/pm	am: midnight to noon. pm: noon to midnight. 12:00 pm is noon. 12:00 am is midnight.
24-hour clock	am keeps the hour (8:05 am = 08:05). pm: add 12 (4:25 pm = 16:25). 12:30 pm = 12:30. 12:30 am = 00:30.
Changing units	60 s = 1 min. 60 min = 1 h. 24 h = 1 day. 7 days = 1 week. 12 months = 1 year. Big to small: multiply. Small to big: divide.
Mixed units	2 h 15 min = 2 × 60 + 15 = 135 min. 135 min = 2 h 15 min (135 ÷ 60 = 2 remainder 15).
Fractions of an hour	Half an hour = 30 min. A quarter = 15 min. 1½ hours = 90 min (not 1 h 50 min).
Days in a month	Knuckles 31, dips 30. February 28 (29 in a leap year). A leap year has 366 days.
Counting on	To find a duration, jump to the next o’clock, then whole hours, then the last minutes. Then add the jumps.
End and start times	End time: add the hours, then the minutes through the next o’clock. Start time: count back.
Timetables	Find the right row and column. Journey time: count on from leaving to arriving. Waiting time: find the next one that has not gone.

Can you…?

I can read an analogue clock to the nearest minute, using past and to.
I can read clocks with Roman numerals and with only a few numbers.
I can put the hour hand in the right place, and read a time when the hour hand is between numbers.
I can write times as digital times with am and pm.
I can change between the 12-hour and the 24-hour clock.
I can change between seconds, minutes, hours, days, weeks, months and years.
I know how many days are in each month and what a leap year is.
I can work out how long something takes by counting on.
I can find a start time or an end time.
I can read a timetable and find journey times and waiting times.
I know that there are 60 minutes in an hour, not 100.

Key terms

Analogue clock: A clock with a round face and hands.
Digital clock: A clock that shows the time in numbers, like 4:35.
Hour hand: The short, thick hand. It shows the hour.
Minute hand: The long, thin hand. It shows the minutes.
Past: After the hour. 20 minutes past 3 is 3:20.
To: Before the next hour. 20 minutes to 4 is 3:40.
Quarter past / quarter to: 15 minutes after the hour / 15 minutes before the next hour.
am: The time from midnight to noon (the morning).
pm: The time from noon to midnight (afternoon and evening).
Noon: 12 o’clock in the middle of the day (12:00 pm).
Midnight: 12 o’clock at night (12:00 am, or 00:00 on the 24-hour clock).
24-hour clock: A clock that counts the hours from 00 to 23 and has no am or pm.
Roman numerals: Numbers written with letters: I, V, X ... Some clocks use them.
Second: A very short unit of time. 60 seconds = 1 minute.
Minute: A unit of time. 60 minutes = 1 hour.
Hour: A unit of time. 24 hours = 1 day.
Leap year: A year with 366 days. February has 29 days. It comes every 4 years.
Calendar: A table that shows the days and dates of the months.
Duration: How long something takes.
Timetable: A table that shows the times of buses, trains, TV programmes or lessons.
Journey time: How long a trip takes, from leaving to arriving.
Convert: To change from one unit to another.