Introduction
There are many different strategies for solving unknown division facts.
Process
Day 1: Drawing Arrays
Watch the following video.
https://www.youtube.com/watch?v=p_XitWjC5Hg
Use the strategy of drawing arrays to solve the following problems.
18 divided by 3
24 divided by 8
32 divided by 4
Choose one of the problems and explain how you would solve it using an array.
Day 2: Using Repeated Subtraction
Watch the following video.
https://www.youtube.com/watch?v=xBlingXK188
Use the strategy of repeated subtraction to solve the following problems.
12 divided by 3
30 divided by 5
42 divided by 6
Choose one of the problems and explain how you would solve it using repeated subtraction.
Day 3: Using Know Multiplication Facts
Watch the following video.
https://www.youtube.com/watch?v=GhwwwBsfOds
Use the strategy of using known multiplication facts to solve the following problems.
15 divided by 5
36 divided by 6
48 divided by 8
Choose one of the problems and explain how you would solve it using repeated subtraction.
Day 4: Skip Counting
Watch the following video.
https://www.youtube.com/watch?v=lZOf9bHw09Y
Use the strategy of skip counting to solve the following problems.
24 divided by 6
32 divided by 8
49 divided by 7
Choose one of the problems and explain how you would solve it using skip counting.
Day 5: Using Anchor Facts
64 divided by 8.
If 8 x 5 = 40
8 x 6 (is one more group of 8) 48
8 x 7 ( is one more group of 8) 56
8 x 8 ( is one more group of 8) 64
So if 8 x 8 = 64, then 64 divided by 8 = 8
In this example why do you think we start with 8 x 5?
Use the strategy of using anchor facts to solve the following problems.
54 divided by 6
48 divided by 8
56 divided by 7
Choose one of the problems and explain how you would solve it using anchor facts.
Evaluation
You know have had the opportunity to discover there are multiple ways to solve a division problem. Using a four square graphic organizer (or another graphic organizer of your choosing) show that you can solve the same problem in multiple ways. You may choose any division problem you choose.
The following rubric will be used to evaluate your graphic organizer.
GRAPHIC ORGANIZER RUBRIC DIRECTIONS:
Using the following criteria, choose the appropriate number from the following scale that reflects your assessment of the student’s work.
1 = Weak
2 = Moderately Weak
3 = Average
4 = Moderately Strong
5 = Strong
1. The graphic organizer has an appropriate title and labels.
2. The graphic organizer’s lines, boxes, and text are neat and legible.
3. The information in the graphic organizer is accurate.
4. The spelling, grammar, and punctuation of the text on the graphic organizer are accurate.
5. The graphic organizer presents the information in a manner that is easy to follow.
6. The relationships presented in the graphic organizer are correct and clear.
7. The form in which the graphic organizer portrays the information is appropriate to the relationships being represented.
8. The graphic organizer demonstrates an understanding of the topic, its relationships & related concepts.
9. The graphic organizer fulfills all the requirements of the assignment.
10. Overall, the graphic organizer represents the student’s full potential.
TOTAL:
Comments:_______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Conclusion
Multiplication and division are inverse operations.
All division facts can be proven with multiplication.
6 ÷ 2 = 3
Think 2 x ___ = 6 or 2 x n = 6
If you are unsure of the multiplication fact draw an array, use repeated subtraction, skip count or use an anchor fact.
Students who are mathematical thinkers are flexible in their thinking and can solve problems in more than one way.
Credits
Want some extra credit? Take this quiz.
1. Giselle has 40 tomato plants. She wants to put them into 5 rows with an equal number in each row. How many tomato plants will go in each row? (8-2)
A 32
B 20
C 12
D 8
2. There are 54 people going on a trip. They will travel in vans with 6 people in each van. How many vans are needed for all of the people? (8-3)
A 9
B48
C 60
D 64
3. Martin has 32 quarters in his piggy bank. He wants to trade them for dollars. There are 4 quarters in one dollar. How many dollars can Martin get? (8-8)
____________________________________________________________
4. Joe has 72 marbles in 8 bags. Each bag has 9 marbles. Write a division fact that uses these three numbers. (8-4)
_____________________________________________________________
5. Each group of tables in the cafeteria is set up in 3 rows with 3 tables in each row. Mr. Grant needs 27 tables for the open house. How many groups of tables does he need to set up? (8-5)
______________________________________________________________
Teacher Page
For additional information on strategies for solving division problems check out the following sites:
www.youtube.com (search basic division fact startegies)