Lesson 5

The Digital Clock

Est. Class Sessions: 2

Developing the Lesson

Tell Time on an Analog Clock. Begin this lesson with a quick review of telling time on an analog clock. Direct students to use their individual clocks to show 3:30. Have them compare the time on their clock with that of a partner.

Ask:

X
  • When your clock shows 3:30, where is the hour hand pointing? (Possible response: It is halfway between the 3 and the 4.)
  • Where is the minute hand pointing? (Possible response: It is pointing at the 30.)
  • When it is 3:30 how many minutes after the hour of three have passed? (30)

Write the notation 3:30 on a display and remind students that this is one of the ways that you write three-thirty. Remind students that the first number tells you the hour and the number after the colon tells you the number of minutes the minute hand has moved after the hour. Write the notation 4:00 on the display but do not tell students what time you have written. Ask them to read the time to themselves and set their individual clock to show that time. Have each student compare the time on his or her clock with that of a neighbor and explain how he or she decided where to set each hand on the clock.

After students have had a chance to
share, ask:

X
  • What is the time shown on your clock? (4 o’clock)
  • How did you decide where to set your hour hand? (Possible response: The first number in the time showed that the hour was 4, so I set the hour hand on the four.)
  • How did you decide where to set your minute hand? (Possible response: The number after the colon shows the number of minutes after 4. Since the number is zero, the minute hand is pointing at the 60.)

Repeat this activity displaying times to the nearest hour and half hour. After students compare their times with a partner, use similar questions to prompt discussion.

Introduce Digital Clocks. Remind students that up until now they have been practicing telling time using an analog clock. Ask them to think about other kinds of clocks they have seen. Tell them that you are going to share a book about time. Read the book Telling Time by Jules Older. This book begins by explaining why we need to tell time. It then explains different measures for time, and finally the book talks about using digital and analog clocks to tell time. As you read, stop periodically to discuss what you are reading.

Use these or similar discussion prompts:

X
  • What are some of the reasons we need to tell time? (Possible response: Time tells us when things happen and how long things take.)
  • What are some ways we can measure time? (Possible responses: seconds, minutes, hours, days, weeks, months, years, decades, centuries, and millenniums)
  • What are two kinds of clocks that we use to tell time? (digital and analog)
  • What is the difference between a digital clock and an analog clock? (Possible response: The digital clock shows the time using numbers and the analog clock has hands that point to the hours and minutes.)

After you finish reading the book, set the digital clock to 6:30 and display it for students. Ask students to set their individual clocks to show the same time. As in the previous activity, direct each student to compare the time set on his or her individual clock with that of a partner and explain how he or she decided where to set each hand.

Ask:

X
  • What time does the digital clock show? (6:30)
  • How did the display on the digital clock help you decide where to set each hand on your individual clock? (Possible response: The display on the digital clock is the same as the way we write the time. Or, the digital clock shows that the hour is six and that thirty minutes have already passed.)
  • Explain which clock, digital or analog, you think is easier to use to tell time. (Answers will vary but many students may feel that a digital clock is easier to use since you can simply read the time from the display.)
  • Why do you think it is important to be able to tell time using both a digital clock and analog clock? (Possible response: You might be in a place that only has one kind of clock so you need to know how to read both. Some watches are analog and some are digital.)

Direct students to the Digital and Analog Clocks pages in the Student Activity Book. Display the first page of Digital and Analog Clocks. After students work independently or with a partner to complete Question 1, ask them to use the display to share their solutions and explain how they decided which clocks matched. Assign Check-In: Questions 2–3 to students to complete independently.

X

Use Check-In: Questions 2–3 on the Digital and Analog Clocks pages to assess students’ abilities to read and write time to the nearest hour and half hour using analog and digital clocks [E4].

Adventure Book:
Student Activity Book: 445 446
Answers
X
SG_Mini
+
X
SG_Mini
+
Master: