Miss M. Carmelle Nesbitt

7th Grade Math

Friday, June 11, 2010

Period: 3

Objectives:

  • TSW review adding and subtracting positive integers, negative integers, and positive and negative integers combined (DOK 2, 1b)
  • TSW recite what PEMDAS stands for. (DOK 1, 1a)
  • TSW simplify problems using the order of operations. (DOK 2, 1a)

Materials:

  • Pencil and paper, LCD projector, computer w/ PowerPoint, dry erase markers, erasers, red (-) and yellow (+) “chips,” “answer cards,” worksheets

Bell Ringer:

  • Review of Wednesday’s lesson on adding and subtracting integers by using worksheet. (15 min)
  • Review materials for the day. (answer cards, index cards, chips, worksheet)
  • KCO Method (Keep, Change, Opposite)
  • TTW introduce the KCO Method for subtracting integers.
  • (START)“Good morning class. After checking the homework assignment from Wednesday night, I realized that many of you aren’t clear about subtracting integers. I apologize if the song confused you. (CLICK)Today for our bell ringer, we are going to review the rules for adding integers and I will introduce a shortcut for subtracting integers called KCO, which stands for Keep, Change, Opposite. This method can only be used for subtraction only!
  • “Let’s take the problem: -12 – 1. Because this is a subtraction problem, we can use the KCO Method. The KCO Method says we should keep the sign of the first term, change the sign of the middle term, and make the last term it’s opposite, then solve.
  • Volunteers: “So for this problem, what would we change the sign to? What would we change the 2nd term to?(CLICK)
  • “So our new equation is -12 +(-1)
  • “Please use your answer cards to show me the answer for this problem. -13 (CLICK)
  • “Now let’s do #1 from your worksheet together. (CLICK)20 – (-5). Because this is a subtraction problem, we can use the KCO Method. The KCO Method says we should keep the sign of the first term, change the sign of the middle term, and make the last term it’s opposite, then solve.
  • Volunteers: “So for this problem, what would we change the sign to? What would we change the 2nd term to?(CLICK)
  • “So our new equation is 20 + 5.
  • “ Again, please use your answer cards to show me the answer for this problem.” 25 (CLICK)
  • (CLICK)“Can we use the KCO Method for the following problems? Why or why not?”
  • NO, YES, YES (Subtraction only!)
  • Red and Yellow Chips Method
  • TTW pair students in groups.
  • TTW introduce checking your work using the Chip Method.
  • (CLICK)“Now I will show you all how to check you addition and subtraction using the Chip Method. Please take the red and yellow chips from your envelope. Each yellow chip represents a positive 1, and each red chip represents a negative 1.”(CLICK)
  • “So let’s solve our problem from earlier using the Chip Method. The equation was -12 – 1. We used the KCO method (CLICK)and changed the equation to -12 + - 1. Using our chips, how do you think we could represent -12?
  • Wait. Volunteers? Answer Cards.
  • “-12 and -1. Count the chips…answer is -13. (CLICK)
  • Let’s do another. (CLICK)1 + (-14). One positive chip. 14 negative chips.
  • When you have a positive and negative pair. They cancel one another out. So this pair is dead. (CLICK)
  • We will count the chips remaining. What’s your answer? -13”(CLICK)
  • TSW complete worksheet with partner. (8 min)TTW walk around the room and check for understanding.
  • TTW review worksheet using answer cards.
  • Questions?
  • ”Now let’s get to the meat of the lesson. As I mentioned earlier, today I will teach you all about the order of operations.“

Set: (5 min)

  • TTW compare the OoO to everyday life by having students order the way in which we have dinner at a restaurant.
  • “Many things in our life have order. For instance, when we prepare to come to school. First we have to wake up, put on clothes, get in the car, drive to school, go to class, leave school. And repeat it the next day! What about going to a restaurant?”
  • 6 chosen volunteers to hold random cards detailing a dining out experience.
  • TTW facilitate a discussion with students to arrange the cards in order.
  • “Thank you for volunteering.” Place cards on the board.
  • “The beginning letters of each of these cards brings us to PEMDAS. The acronym for the OoO.(CLICK)

Procedure: (17 min.)

1. Ask students what PEMDAS means?

  • TTW write their responses on the board from the first letter on PowerPoint.

2. Explain what each letter means.

3. Do 3 sample problems. Work problems out completelyyy.

  • (3+2)2 =
  • ((7-2+4)-3)*2 =
  • =

4. TSW complete the last 3 problems on the worksheet.

5. Review worksheet using answer cards.

Closure: (3 min)

  • “Today we learned about the KCO and Chip Method and the Order of Operations.
  • Volunteers:
  • What is the KCO Method?
  • When is it used?
  • What is the chip method? Which is yellow? Which is red?
  • What does PEMDAS stand for?
  • On your index card, write 3 things you learned today or liked today and have a clear understanding of.
  • On the back of the card, write a concept you are still a little confused about.
  • Next period, Sedlacek will review the material for the test with you all.