Reading Clocks to the Half Hour - Teaching Strategies: 1.75

As noted in the Indicator of Progress Reading the hour on a clock (1.25) much of the teaching of reading an analogue clock will occur incidentally throughout the day as the teacher points to the classroom clock. Previously, the focus of reading analogue clocks was on the hour hand, but now information from the minute hand is co-ordinated with this.

The specific teaching strategy is to remind students of the importance of the hour hand and to then focus their attention on the minute hand when it is pointing close to, as well as directly at, the 12 or the 6. At this stage 8:30 is known as another name for half past 8, and not linked by all students to the fact that 30 is half of 60.

Activity 1: Making a clock face emphasises equal spacing of numbers on a clock face and the division of the clock face into halves and quarters. Reading the time using only an hour hand is revised. This activity can be revisited when students are learning to read the clock to the quarter hour.

Activity 2: Co-ordinating both hands shows students how the hour and minute hands are linked to show o’clock and half past times. Students use self-made clocks and teacher has a geared clock.

Activity 3: Linking analogue and digital clocks makes explicit connections between analogue and digital clocks.

Activity 4: Setting up a clock corner involves children displaying various ways of measuring time.

Activity 1: Making a clock face

This activity draws attention to the equal spacing of the numbers around the clock face. Print the template clockface and copy for each student, using light card if possible. Each student will also need a split pin and 12 paper clips. The clips are used to position the 12 numbers temporarily until they are equally spaced.

Students cut out the clockface, the 12 numbers and the clock hands.

Fold the circle into quarters and mark the centre of the circle for later use. Note: this folding links to the fraction ¹/₄ in Number.

Students place 12, 3, 6 and 9 on their clockface using paper clips to hold in position.

Now position the other numbers between 12, 3, 6 and 9 using paper clips to hold in place.

Compare and adjust the position of the numbers around the circle to ensure equal spacing before gluing.

Add only the hour hand. For more about this ‘one handed clock’ see Measurement - Reading the hour on a clock: 1.25.

Remind students that the hour hand points directly at a number on the hour (o’clock). For example, What time does this clock show? (4 o’clock).

Review how the hour hand moves from one number to the next, showing how much of the hour has passed.

Sample questions:

• Move your hour hand so that it points half way between 3 and 4. What time is this? (half past 3).
• Move the hour hand so that the time shown is just before 10 o’clock.
• Move the hour hand so that the time shown is just after 10 o’clock.

Conclude by noting the minute hand helps read the time more accurately.

Activity 2: Co-ordinating both hands

In this activity, students are asked to show a time on their clocks. They need to predict where both hands will be. Students will need to attach both the hour hand and the minute hand to the centre of their self-constructed clock face with a split pin.

It is important for the teacher to have a geared clock for this demonstration so that students can see the correct placement of the hands. The advantage of a geared clock is that the hands are linked and as the minute-hand is rotated, the hour hand will move appropriately. This is in contrast to the students’ made clocks, where the hands are independent and can be placed incorrectly (e.g. see the incorrectly placed hour hand for 10:30 shown in Illustration 1 above).

Step 1: Watching the hands move on a geared clock.

Students will already know that both hands on a clock move, and that the hour hand takes one hour to move from one number to the next. They may not yet understand that both hands move in the same direction (clockwise) and that the minute hand takes one hour to make a complete revolution. These ideas are first drawn out during a demonstration using a geared clock. Begin by eliciting what students already know about the movements of the hands of the clock, demonstrate them. Some students can be asked to focus on the hour hand, whilst others focus on the minute hand. For example, get a few students to watch the hour hand starting from 2:00 and to say “stop” when it reaches the number 3. Other students watch the minute hand and explain its motion. Swap roles.  Repeat, asking the students to stay ‘stop” when the hand has gone half way between two numbers, when the minute hand students will have observed it move towards the 6. Repeat, asking the minute hand students to say ‘stop’ when their hand has gone halfway around (i.e. to the 6) and ask the hour hand students what they observe. Link this to the common phrase “half part 2” and also to 2:30. Some students will be able to explain that 30 is half of 60.

Looking carefully at the movement of the hands enables students to visualise and predict movements for other times.

Step 2: Hours and half hours

Students are asked to predict by moving the hands of their clock, before the teacher demonstrates on the geared clock. For each time given to the students, focus explicitly on the position of each hand.

Examples	Where is the hour hand pointing?	Where is the minute hand pointing?
Show me 1 o’clock. Is it the same as my clock?	"directly at 1"	"no turning has started yet, so it points at 12"
Show me half-past 1. Is it the same as my clock?	"half-way from 1 to 2"	"half a turn, so it points at 6"
Show me 2 o’clock. Is it the same as my clock?	"directly at 2"	"full turn completed, so it points at 12"

Step 3: Approximate times near hours and half hours

Students are asked to predict by moving the hands of their clock, before the teacher demonstrates on the geared clock. There are many possibilities for the approximate times being discussed: for example, “just after 3 o’clock” might be any time from 3:01 (the minute hand has moved just after the 12 and the hour hand would not appear to have moved) to 3:10 (the minute hand has moved to the 2 and the hour hand would have moved slightly).

For each approximate time given to the students, show a range of possible times on the geared clock, including both the situations where the minute hand points directly to a number, as well as when it points between numbers.

Examples	Where is the hour hand pointing?	Where is the minute hand pointing?
Show me 3 o’clock.	"directly at 3"	“pointing directly at the 12"
Show me a time just after 3 o’clock. I will start to move the minute hand on my clock - let me know when it matches your clock.	Example 1: approximately 3:01
	"still directly at 3"	"just a little turning after the 12, so between the 12 and 1"
	Example 2: approximately 3:07
	"just after the 3”	"between the 1 and 2"
Show me a time just before half-past 3. I will start to move the minute hand on my clock - let me know when it matches your clock.	Example 1: approximately 3:25
	“about halfway from 3 to 4”	“pointing directly at the 5”
	Example 2: approximately 3:29
	“about halfway from 3 to 4”	“between the 5 and the 6, just before the 6”
Show me half-past 3.	“halfway from 3 to 4	“pointing directly at the 6”
Show me a time just after half-past 3. I will start to move the minute hand on my clock - let me know when it matches your clock.	Example 1: approximately 3:32
	“halfway from 3 to 4”	“between the 6 and the 7, just after the 6”
	Example 2: approximately 3:40
	“between 3 to 4, closer to 4”	“pointing directly at the 8”
Show me a time just before 4 o’clock. I will start to move the minute hand on my clock - let me know when it matches your clock.	Example 1: approximately 3:50
	“between 3 to 4, closer to 4”	“pointing directly at the 10”
	Example 2: approximately 3:58
	“almost directly at the 4”	“between the 11 and the 12, just before the 12”
Show me 4 o’clock.	“directly at the 4”	“pointing directly at the 12”

Activity 3: Linking Analogue and Digital Clocks

Have two classroom clocks – analogue and digital. Throughout the day, ask the students to look at the (analogue) classroom clock to read the hour and half hour information and then mimic this on their self-constructed analogue clocks or shoebox digital clocks with a focus on times close to the hour and half hour. In addition, provide a digital clock so that students can link the digital display to the analogue clock. Students should note the position of both the hour and minute hands and then mimic these on their own clocks, see: Indicator of Progerss: Reading the hour on a clock (1.25).

Ask questions about what time the classroom clocks (analogue and digital) show (e.g. 10 o’clock, half past 11, 10:00 and 11:30).

Ask students to make future times on their own clock. For example, if students make 1:30, the time when we will be going to PE, they can check it on the real clocks when the time arrives.

Extend the activity by asking students to read times close to the half hour or hour, and not exactly on it (e.g. just after 10 o’clock, just after half past 11, a few minutes before 3 o’clock). Link these times to digital equivalents, such as 10:02, 11:32. The more demanding one will be linking a few minutes before 3 o’clock to 2:57 etc, and this can be done last.

Activity 4: Setting up a clock corner

Make a clock corner and discuss the many aspects of measuring time.

Questions might include:

• How do you use an egg timer? How does it work? (Stress that the sand always takes the same time to go through the narrow section in the middle). Students could make their own ‘egg timers’ by putting different amounts of sand in a plastic ice cream bucket with a small hole in the bottom and timing how long it takes to go through. Discuss how if there is more sand it takes a longer time to go through the hole, how a bigger hole would let the sand go through in less time (more quickly), and how the time for the sand to go through the hole would be longer if the sand got wet. Vocabulary about time, quantity and rate is involved.
• Could I use the egg timer to tell me when it is time to go to ballet? How, or why not?
• This egg timer is labelled 3 minutes. What other clock or timer can we use to check this?
• Which of these clocks would be best for timing a short running race? Why?
• Which of these clocks and timers would help me find out how many seconds I can stand on one leg? Can I use the clock radio? How, or why not? Can I use the metronome?