Finding Time Intervals

• How do I tell the hour on a clock?
  Use a model clock to point out the hour hand and minute hand. Remind children that the hour hand is shorter. Move the minute hand to each number on the clock, having children count aloud by fives. Point out that 60 minutes pass during one hour. Place the minute hand at 12, and then move the hour hand to different numbers. Read each time on the hour together, for example: seven o'clock, eight o'clock, nine o'clock.

• How do I write the time I see on a digital clock?
  Use an analog clock to show 8:00. Ask children to explain how they know the time. Then write the number 8, pointing out that it names the hour. Write a colon and explain that it separates the hour from the minutes. Write two zeros, explaining that the zeros mean time exactly on the hour. Point out that the time on the analog clock—and the time that you wrote—both mean eight o'clock. Repeat with 8:30. Have children practice writing the corresponding times using numbers and colons, as you show these times on an analog clock.

• How do I tell how much time has passed?
  Use an analog clock to show how much time has passed. Explain that a movie might begin at 7:00 and end at 9:00. Show 7:00 on the analog clock. Then move the minute hand and hour hand to show 8:00. Ask how many minutes and how many hours have passed. Then move the hands to show 9:00 and repeat the questions. Point out that two hours have passed since 7:00, so the movie lasts two hours.