Birthday Party

Birthday Party

Auto-markingPencil and paperOnline interactive
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about working out word problems.
 
Ruby had a birthday party.
She invited some friends.
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Question 1Change answer

a)  There were 5 bottles of orange drink at the party. 
     Ruby and her friends drank 3 bottles of orange drink.
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     How many bottles of orange drink were left over?

Question 1Change answer

b)  There were 8 children at Ruby's party.
     There were 5 girls.
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     How many boys were at Ruby's party? 

Question 1Change answer

c)  There were 17 balloons at the party.
     Ruby gave 4 balloons to her friends.
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     How many balloons did she have left?

Question 1Change answer

d)   Ruby's dad cut the cake into 14 pieces.
      Ruby and her friends ate 9 pieces of cake.
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     How many pieces of cake were left? 
Task administration: 
This task can be completed online or with pencil and paper with auto-marking.
Level:
1
Keywords: 
Description of task: 
Students solve subtraction word problems.
Curriculum Links: 
Links to Numeracy Professional Development Projects
Book 5: Teaching Addition, Subtraction, and Place Value: pages 17-20, 32, and 42-43.
Learning Progression Frameworks
This resource can provide evidence of learning associated with within the Mathematics Learning Progressions Frameworks.
Read more about the Learning Progressions Frameworks.
Answers/responses: 
    Y2/3 (03/2017)
a) 2 very easy
b) 3 easy
c) 13 easy
d) 5 easy
Based on an online sample of Year 2 and 3 students
Teaching and learning: 
This resource has an increasingly difficult set of subtraction problems using numbers in the range 0-20.
The intention is for students to apply subtraction strategies to solve the problems.  Some students may use complementary addition/reversibility to solve the problems.
Group discussions can assist students to build their repertoire of strategies. 
 
Diagnostic and formative information: 
  Common error Likely reason Likely misconception/s
b)
13
Adds, rather than subtracts, the two numbers.
Misreading the problem
Students has misread the problem.
May have assumed that when there are two numbers in a problem they should be added together.
c) 
d)    
14
6
Counts back but includes the starting number, i.e. 17, 16, 15, 14 or 
14, 13, 12, 11, 10, 9, 8, 7, 6
Adding instead of subtracting
Student may have yet to grasp counting back as a subtraction process.
c) 
3
Calculates 7 - 4 rather than 17 - 4.
Errors applying subtraction strategies
Student may have misread the numbers in the problem, or has subtracted the tens and ones separately, but omitted to include the 10 back into the answer.
Next steps: 
Misreading the problem:
First, check that students have read the question carefully.
If necessary, have students work in pairs, reading the question together and recording how to solve the problem by using materials, symbols, images or a number sentence.
Students can practise this skill with a range of word problems without needing to solve them.
 
Adding instead of subtracting:
In small groups or as a class, read out a word problem.  Have students hold up the correct operator needed to solve the problem (+, – initially, moving on to × and ÷ as appropriate).
Making Number Sentences is a Level 2 resource that could be used with individuals, groups or the whole class to practise this skill.  For further extension or ideas, Making Number Sentences II and Number Sentences and Story Problems are similar Level 3 resources.
 
Errors applying subtraction strategies:
Use materials such as counters, beans, plastic animals etc, to 'act out' the scenarios in this resource, and/or other similar scenarios.
 
For students who need more time to work with numbers below 5, try the ARB resource Subtraction Fun (Level 1) which focuses on subtraction problems using numbers between 0 and 5 with different parts of the equation missing.
 
The ARB resource Vegetable Soup (Level 1) is a parallel resource with a similar range of subtraction problems.
 
The following resources provide further extension opportunities: