## Time Flies When Math Is Fun

### Cindy Jacobs

#### Description

Students will use demonstration clocks and play a game to determine elapsed time.

#### Objectives

The student solves real-world problems involving measurement using concrete and pictorial models for the following: length (for example, half-inch, centimeter); weight (for example, pound, kilogram); time (fifteen-, five-, and on-minute intervals); capacity (for example, cup, liter); temperature (Fahrenheit and Celsius); angles (right).

The student uses schedules, calendars, and elapsed time in hour intervals to solve real-world problems.

The student using real-world settings, objects, graph paper, or charts, solves problems involving estimated measurements including the following: length to nearest inch, centimeter; weight to nearest pound, kilogram; time to nearest half-hour interval; temperature to nearest five-degree interval; and money to the nearest \$1 or \$10 (combination of coin and currency).

#### Materials

-Large Demonstration Clock
-Demonstration clocks (enough for each student)
-Chalk
-Number Cube
-Paper
-Pencils

#### Preparations

1. Gather materials needed for this lesson.
2. Clocks need to purchased or gathered in advance.

#### Procedures

1. Review the hour hand and minute hand. Also review telling time to the hour, half hour, quarter hour, and minute.

2. Tell students that you (teacher) are going to show students some times on a demonstration clock. They will need to determine what time the clock shows and what time it will show after a determined amount of time has passed. This is called elapsed time.

3. Position the hands of the clock to show two o'clock. Ask students what time the clock shows. Ask them what time will it show in two hours and forty-five minutes (4:45). Rotate the hands clockwise and demonstrate counting on in hours and five minute intervals. Ask students if they were to add another sixteen minutes to 4:45, what time the clock would show. (5:01). Demonstrate counting on by five minute intervals and minutes. Do several more examples.

4. Give students a demonstration clock.

5. Write the times (below) on the chalkboard and have students tell you what time each will show in 5 minutes. Have them demonstrate on their clocks.

1. 9:00
2. 9:35
3. 8:55
4. 9:28

6. Next, write these times on the chalkboard and have students tell you what time each will show in 20 minutes. Again, have them demonstrate on their clocks.

1. 12:00
2. 8:15
3. 3:30
4. 6:07

7. Tell students that we are going to play an elapsed time game that is a lot of fun. Divide students into groups of four or five.

8. Give each student a sheet of paper.

9. Give each group a clock and a number cube.

10. Instruct each group to position their clock hands to show twelve o'clock.

11. Tell students to each to take a turn within their group rolling the number cube to determine which one will go first. The student with the highest number goes first and the student with the second highest goes second, etc.

12. Students will each take turns rolling the number cube. The number each student rolls will be added to the clock's time beginning at twelve o'clock and recorded on his or her individual paper. For example, if a student rolls a four on the first roll, he or she will add a four to the number twelve to make it 12:04. If a five is rolled on the second roll, the student will add five more minutes making the time 12:09. It is important that students keep up with the minutes (numbers) rolled each time on their scratch paper. Students must position the hands of their clock and say the correct time aloud each time.

13. Each player will play a total of five turns. After each has completed the five turns, the player with the greatest amount of elapsed time will be the winner.

14. You may want to play this game several times.

15. After the game, write the following times on the chalkboard (not the answers in parenthesis):

1. 6:00 (6:30)
2. 7:30 (8:00)
3. 11:00 (11:30)
4. 10:10 (10:40)
5. 12:25 (12:55)
6. 2:50 (3:20)
7. 9:15 (9:45)
8. 3:45 (4:15)
9. 4:20 (4:50)
10. 6:24 (6:54)

16. Have students copy the times (above) on their paper. Have them record beside each time shown the time each clock will show after 30 minutes have passed. They should use a demonstration clock to figure out their answers.

17. Collect papers for assessment purposes.

#### Assessments

1. Mastery and non mastery will be informally based on observation of students while performing excercises in elapsed time. 2. Mastery or non mastery will be based on getting 8 out of 10 problems regarding elapsed time correct.

#### Extensions

This game could be played where the student with the least amount of elapsed time is deemed the winner. If you do not have enough demonstration clocks for individual use, you could have students make clocks using paper plates, etc.