:What's My Number
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Approach: One to one  Level: Year 4 and year 8
Focus:   Verifying and proving
Resources: 3 cards
172KB
Questions / instructions:

I am going to show you some cards with numbers that are missing.

   
% responses
2005 ('01)
Y4
Y8
Hand student card 1.
Card 1
6 = 4 + _
 
One child thinks that the missing number is 10.
1. Do you think that child is correct?
no
60
90
2. Why do you say that?
10 + 4 = 14
17
35
 
4 + 2 = 6
26
45
any other valid reason
10
10
Hand student card 2.
Card 2
6 + 2 = _ + 5
3. What is the missing number?
3
11
54
4. Why do you say that?
6 + 2 = 8 and 3 + 5 = 8
9
48
 
any other valid response
2
8
YEAR 8 ONLY:
Hand student card 3.
Card 3
3 + _ = _ + 6
   
5. What do you think the missing numbers could be?
valid pair of numbers such as (3, 0) or (4, 1)
•
59
6. Could you have any other numbers?
yes
•
69
7. Why do you say that?
clear generalisation showing that the second number
must always be 3 less than the first missing number
•
7
 
explanation based on specific examples
•
24
some explanation given but not clear
•
25
any other response
•
44
Total score:
8
•
7
 
6–7
•
39
4–5
9
17
2–3
44
30
[Note: Maximum score of 4 for year 4]
0–1
47
8
Commentary:
Students at year 8 level were quite proficient with the simpler questions and over half could handle the more complex ones. The task was more difficult for the year 4 students.
 
Chapter Graphic
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