ADDITION AND SUBTRACTION PROBLEM SOLVING Nick Meyer and

ADDITION AND SUBTRACTION PROBLEM SOLVING Nick Meyer and Kathy Jones, District Elementary Math Coaches October 24, 2017

overview 3 Examine addition and subtraction problem types 1 4 2 Model concrete and pictorial representations 3 Investigate progression across grade levels Understand how parents can help

4 Create a Word Problem u On a sticky note, write a one-step addition or subtraction word problem. u Save your sticky note for an activity that we will do in a few minutes.

5 Addition/Subtraction Problem Types

6 Your Sticky Note u Review the addition or subtraction problem you wrote on your sticky note. u To which problem type does it align? ?

7 Continuum of Representations

8 Carson brought 17 crackers for snack. He ate 9 crackers. How many does he have now? Carson

9 Carson brought 17 crackers for snack. He ate 9 crackers. How many does he have now?

10 Carson brought 17 crackers for snack. He ate 9 crackers. How many does he have now?

11 Ducks Some ducks were in the lake. Then 156 more ducks came to the lake. Now there are 234 ducks in the lake. How many ducks were in the lake to start with?

12 Try It! Enoch has 407 Lego pieces. He used 129 pieces to build a model spaceship. How many Lego pieces does Enoch have left?

13 “Compare” problems Ali has $9. Maria has $5. How many more dollars does Ali have than Maria? Diana has 4 fewer video games than Beatrice. Diana has 7 video games. How many video games does Beatrice have? There are 59 more boys than girls on the playground. If there are 136 boys on the playground, how many children are on the playground?

14 Much larger numbers… In all, 30, 436 people went skiing in February and January. 16, 009 went skiing in February. How many fewer people went skiing in January than in February?

15 Much smaller numbers… Leslie has 1 liter of milk in her refrigerator to drink today. She drank ½ liter of milk for breakfast and 2/5 liter of milk for dinner. How much of a liter of milk does Leslie have left to drink with her dessert?

16 How can you help? u Ask your student about his/her math drawing. u Where does each quantity appear? u Ask your student about his/her method for adding and subtracting. u How do they decide to break the numbers into manageable parts?

questions and answers 17 ? We are happy to answer any questions.