Prior to class, draw or tape a number line (-20 to 20) in the front of the classroom. Prepare two stacks of numbered cards (-10 to -1 and 1-10). Have a string and a tie or scarf for the tug of war game. Divide the class into 2 groups, the Perky Positives and the Noisy Negatives. Create a transparency of the Tug of War chart so that it can be displayed on the overhead projector in the classroom. It will be used to keep track of the game. The Tug of War chart can be copied for each student so that they have a copy of the questions and answers. Choose 2 students to hold the string tight under the number line. Choose 2 students to be in charge of shuffling the Positive and Negative Cards.
A computer with Internet access is needed for this lesson. A computer lab works best but if one is not available, the BrainPOP Web site can be displayed for the class using an LCD projector. Make sure the BrainPOP Web site is bookmarked on the computer(s).
Each student will need a pencil, a piece of paper, and a copy of the Integers Worksheet, the Rules for Adding Integers, and the Exit Quiz.
Teacher Presentation & Motivation:
Ask students to contemplate the following questions. (Don’t elicit answers.)
* What happens in football in you loose 6 yards in one play and gain 14 yards in the next?
* During January in Alaska, the average temperature at night is -10 degrees. During the day, the temperature rises 20 degrees. What is the average temperature in Alaska during the day?
* Suppose you thought that you had $37 in your checking account and wrote a check for $25. On your way home, you remembered that you had withdrawn $20 the day before. What is the minimum amount that you must quickly deposit to avoid a penalty?
* Announce that today we are going to play a game of “Tug of War” on a number line to examine the concept of adding integers. Pay close attention to the movement of the tie to see if you can predict the answers and determine the rules. The skill of adding integers will help you answer questions like the “Real Life” ones above.
Activity 1 - Integer Tug of War!
The tie (or scarf) begins at zero. Choose a positive number from the number cards. Move the tie to the right to the number on the number line. Choose a negative number from the number cards. From the position of the previous positive number, move the tie to the left on the number line. Where do we wind up? Record the three numbers on the chart. The two student helpers (who are holding the string tight) move the tie back to the zero position after each round.
One Perky Positive chooses a number from the positive number stack and moves the tie to that number on the number line. A Noisy Negative will choose a number from the negative stack and move the tie to the left from where the Perky Positive left it. The answer is the result. Students should record the numbers on their individual charts as the teacher records the problem on the large chart.
When the numbers have been exhausted, read the problems on the chart aloud. Ask students to share ideas and talk with the people in their group to see if they can come up with a “Rule for Adding Integers.” The teacher should elicit ideas from the students. With guidance from the teacher, have the students formalize the rules and then give them each a copy of the Rules for Adding Integers worksheet.
Complete several more problems with the student predicting the outcomes. Continue modeling if necessary.
Activity 2 - BrainPOP Video Clip - Adding and Subtracting Integers
Students will view the BrainPOP video clip on adding and subtracting integers. If the class is more advanced, students may view the video clip entitled, Adding and Subtracting Integers Advanced. A computer lab setting works best. If one is not available, display the Web site using an LCD projector in the classroom. Students can answer the questions displayed on the Web site while the video clip is loading.
Focus for Media Interaction
Focus for Media Interaction: The focus for media interaction is a specific task to complete and/or information to identify during or after viewing of video segments, Web sites or other multimedia elements.
By the end of the clip, students should be able to define the rules for adding and subtracting integers.
What will your students be responsible for while viewing this piece of multi-media or video?
Students will answer the questions given on the Web site while they are waiting for the video clip to load. As they view the integer video clip, students should take notes in order to define the rules for adding and subtracting integers.
Post Viewing Activities
How will students utilize the information they gathered while viewing the multi-media or video?
The teacher will have several students read the rules for adding and subtracting integers. Have students give examples.
Activity 3 - Integers Worksheet
Distribute the Integers Worksheet. Students may work in pairs while completing this worksheet. Circulate among the students to offer individual assistance as necessary. Prompt students to create their own number lines (if necessary). Check the worksheet together.
Activity 4 - Exit Quiz
Prior to distributing the quiz, be sure to ask students if they have any questions. Distribute the Exit Quiz to each student. The students will complete this quiz independently. The teacher will collect the quiz for assessment and will return them to the students the following class.
Have the students verbally review the rules for adding integers. Finally, the teacher will lead a class discussion that answers the class challenge question posed at the beginning of this lesson.