Math Background

Lesson: Schedules and Elapsed Time
Introducing the Concept

“Just a minute” is a phrase that children hear all the time, and it is often used incorrectly. Children need to develop a firm understanding of what a minute is and how it relates to an hour. They need to know that a minute is made up of 60 seconds and that an hour is made up of 60 minutes. To develop these concepts, your children need to develop a feel for the length of a minute. They need to realize that a minute is not long, but it is not as short as a second, either. Developing these concepts will help your children have a better understanding of time.

Materials: index cards; 2 for each child.

Preparation: none

Prerequisite Skills and Concepts: none

Pass out 2 index cards to each child. Have children write M on one and H on the other.

  • Say: Today we are going to talk about time, and learn about a minute and an hour.
  • Ask: How many of you have ever heard someone say “just a minute?”
    Check for raised hands.
  • Say: Today you are going to find out how long a minute really is, and then you can check to see if people really do get to you in “just a minute.”
  • Say: I want you to close your eyes. I am going to time one minute on my watch. I want you to stand up when you think a minute has passed. I will tell you when one minute has passed.
    (Time a minute on your watch.)
  • Say: It takes about a second to say “one thousand one” or to snap your fingers. A minute is made up of sixty seconds. So you can snap your fingers about 60 times in a minute. You can also say “one thousand one” about 60 times in a minute.
  • Say: Let's time a minute again. Put your heads down, close your eyes, and stand up when you think a minute has passed.
    Repeat the minute activity, and check this time to see that children are standing up close to a minute.
  • Ask: How did you decide when a minute had passed?
    Discuss their answers.
  • Say: Now that you know how long a minute is, let's talk about how long an hour is. An hour is 60 minutes. So, if you think about a minute 60 times, then you will have estimated about an hour. An hour can feel like a long time, or it can feel short, when you are having fun. Some things that might take an hour to do are taking a nap, riding a bike, or cooking dinner.
  • Say: Now I am going to tell you an activity, and you are going to hold up either your M card for minute, or your H card for hour.
  • Ask: Would it take you an hour or a minute to brush your teeth? (M)
  • Ask: Would it take you an hour or a minute to mow your lawn? (H)
  • Ask: Would it take you a minute or an hour to get a drink from the fountain? (M)
  • Ask: Would it take you a minute or an hour to eat dinner and clean up the table? (H)
    Repeat this activity with as many scenarios as you can.
  • Ask: Think about a second, a minute, and an hour. Which is the shortest unit of time? (second) Which is the longest? (hour) How many seconds in a minute? (60) How many minutes in an hour? (60)
  • Say: Today we talked about seconds, minutes and hours. We learned that an hour is longer than a minute, and a minute is longer than a second. We know about how long a minute is, so the next time someone says they are coming in a minute, you can let them know if they are right!

Houghton Mifflin Math Grade 2