Educational Activity

Title: Telling Time... 24 hours a Day!

This activity can assist teachers with presenting a lesson on 24-hour time.


During this exercise, students will:

o Recognize that there are 24 hours in a day

o Translate am/pm time into 24 hour time

o Convert 24-hour time into am/pm time

o Identify the approximate times of common events in their lives

Materials needed:

* print out of questions for each student or group of students

Introductory Discussion Narrative.

It was close to dinner time, as Linda and Tom sat working at their tables in the ship's main lab.

'Gggggrrrrrhhh - glug glug glug glug!' came a sudden sound.

"What was that?" said Tom, as fell off of his stool in surprise.

"I don't know, but I heard it too." remarked Linda.

After a moments pause, a shy little voice remarked "It was me."

Linda and Tom looked down, and there, under the table, was Soupy, hanging upside down with his head bowed in embarrassment.

"You said that?" asked Tom in surprise.

"I didn't say it." explained Soupy, "my belly sort of did it."

"Oooh" said Linda, "you must have had too many apple cores from your peeling session with Charlie this morning. I figured you would have digested everything, it being so late in the afternoon already."

"No!" protested Soupy, "I didn't eat too many apples, in fact I didn't eat any!"

"How come?" asked Tom.

"I showed up at one o' clock like Charlie told me to, but he wasn't there, and there were no apples left, just apple sauce already sealed in jars. I didn't even eat lunch because I was so excited, I wanted to save up."

"Soupy..." said Tom,


"...let's see the note Charlie gave you." Soupy fumbled around inside of his leathery wings, and then produced a little scrap of paper. Tom took it and read it, and gave soupy a sympathetic look of consolation. "I think I know what happened, Soupy. It says here on the note:

Hi Soupy, I'm on a very quiet shift this week, and so I've offered to help peel and core some apples in the kitchen at 0100 tomorrow. I figured that since you're a fruit bat, you might want to help, and eat some apple cores as we go along! They'll be plenty of left overs!

Cheers, Charlie.

"Soupy you said that you came to kitchen right after lunch?" continued Tom.

"Yes, and Charlie wasn't there. I asked Hasheem where he was, and Hasheem laughed and said 'sleeping of course!'. And now it's 4 o clock and my belly is sooooo hungry!

"Oh, Soupy" smiled Tom, "I think I know what happened... come on" he said lifting him up "on the way to the kitchen we'll teach you a little lesson on time."

Discussion: Use the above story as an introduction into a lesson on 24 hour time. You can use the following questions to start a discussion.

* What do you think happened? Did Soupy's watch go wrong, did he come on the wrong day, the wrong place, or was it something else?

* Soupy said he came at one o clock. Is there only one, one o'clock in a day?

* Why do you think there was a 0 at the start of 0100 in Charlie's note?

Note: You may want to explain to students that living on a ship is a little bit different than on land. For one thing, someone always has to be up to do things like steer and navigate the ship, and at least a few scientists have to be up to keep the research going. That's why we have people split into shifts. This means that even at strange hours like one o'clock in the morning (0100), a few people are awake making sure that everything is going well.

Exercises You may want to use the following two exercises to connect the concept of 24 hour time with the student's day to day life as well as the ship's daily routines.

Exercise #1

Below are common activities that you probably do every day. Write down what time you do each activity in both regular and 24hour time.

TIME: am/pm
Time: 24hour clock
Afternoon Nap
Have Breakfast
Go to School
Have Lunch
Get out of School
Have Dinner
Watch TV
Go to Sleep


Exercise #2

The Ship's Schedule:

The following is a list of some regularly scheduled events on our research vessel. Each event is in 24-hour time. Have students convert each time from the 24-hour format to the am/pm standard.

24hr Time
am/pm Time
Ping Pong Game


Email is sent through a satellite connection

Further Discussion Suggestions

* what are some advantages of using a 24-hour standard vs. an am/pm time standard? [am/pm is not international, it's easy to confuse am and pm, easier to relay and understand over UHF radio for ships and planes, etc.]

* What are some ways of remembering how to convert am/pm to 24-hour time.

* What occupations would find 24-hour time most useful?

Subject Standards:

This activity can address the following educational standard:

Fifth Grade Mathematics: Number Sense and Operations

1.5.17 Interpret the 24-hour clock.