Subtracting Integers w/ Counters: Student Activity Lesson Plan
Subject/Strand/Topic: Math – Number Sense and
Numeration
Key Concepts:
Grade(s) / Course(s):
7
Ontario Expectations:
7m14
subtracting integers using coloured counters
Link: http://www.nearnorthschools.ca/it/PRISMNEO/list.asp?concept=All&grade=7- learning object
http://www.nearnorthschools.ca/it/PRISMNEO/PRISMNEO/SubIntegers.pdf- lesson plan resource (optional)
Required Materials: Pre-Assessment/Answer Key, Student Activity Handout, Student Activity Answer Key, PostAssessment/Answer Key, pencils, calculators
Before Starting: book computer lab so there are enough computers per pair of students
Introduction (~ 10 minutes including pre-assessment)
1. Introduce topic (subtracting integers with counters)
2. Distribute pre-assessment; allow 5-7 min. for students to complete
3. Introduce activity to students (learning how to subtract integers with counters)
Student Activity Handout Explanation (~ 5 minutes)
1. Distribute handout for each student to complete
2. Briefly go over the structure of the handout (Parts A & B) each student will need to bring a pencil to computer
lab
3. Students should have 20-30 min. to complete the handout as they go through learning object
Use of Learning Object with Student Activity Handout (~ 20-30 minutes)
1. Students will work in pairs, each pair at one computer
2. Instruct students to open internet browser and type in the link at the top of their handout in the address
bar; scroll down the page and click on “SubIntegers.gsp”
3. Before starting the activity, allow students 1-2 min. to explore the learning object
4. Make sure the “Select” tool is ALWAYS selected in order to use the sketchpad
5. Students should spend about 15 min. on Part A and 10-15 min. on Part B to complete their handout
6. Have one student on the computer and the other instructing (switch roles halfway through)
7. Circulate around the computer lab; remind students of time constraints and encourage them to finish
8. NOTE: inform students that they proceed to the next activity by clicking on the tabs at the bottom of the .gsp
window. They can also click on “1” to return to the list of activities
(main menu) in non-tabular form
Consolidation (~ 10 minutes including post-assessment)
1. Ask students the following questions at the end of the activity with the learning object:
a. How do you represent zero using coloured counters? (one positive counter (red) and one negative
counter (blue))
b. Does the order matter when subtracting integers? (yes!)
c. How do you subtract negative integers? (you introduce zero coloured counters (1 +ve + 1 -ve))
2. Distribute post-assessment; allow 5-7 min. for students to complete
3. Take up answers from handout
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Lesson Plan
Page 1 of 1
Subtracting Integers with Counters
Name: ___________________________
Birthday: ____________________________
Student Activity Pre-Assessment
6
Instructions: Answer the following questions to the best of your ability. You are not permitted to use a calculator.
Good luck!
1. Solve the following subtraction problems. (4 marks)
a) 7 - (- 4)
b) (- 9) - (- 5)
c) (- 3) - 6
d) 6 - (- 10)
2. The temperature was -10°C on Friday. On Monday, the temperature dropped 3 degrees from Friday’s. Calculate
the difference in temperature. (2 marks)
Subtracting Integers with Counters
Student Activity Pre-Assessment
Name: ___________________________
Birthday: ____________________________
6
Instructions: Answer the following questions to the best of your ability. You are not permitted to use a calculator.
Good luck!
1. Solve the following subtraction problems. (4 marks)
a) 7 - (- 4)
b) (- 9) - (- 5)
c) (- 3) - 6
d) 6 - (- 10)
2. The temperature was -10°C on Friday. On Monday, the temperature dropped 3 degrees from Friday’s. Calculate
the difference in temperature. (2 marks)
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Pre-Assessment
Subtracting Integers with Counters
Student Activity Pre-Assessment
Answer Key
Name: ___________________________
Birthday: ____________________________
6
Instructions: Answer the following questions to the best of your ability. You are not permitted to use a calculator.
Good luck!
1. Solve the following subtraction problems. (4 marks)
a) 7 - (- 4)
b) (- 9) - (- 5)
c) (- 3) - 6
d) 6 - (- 10)
= 11
= -4
= -9
= 16
2. The temperature was -10°C on Friday. On Monday, the temperature dropped 3 degrees from Friday’s. Calculate
the difference in temperature. (2 marks)
(-10) - 3 = -13
The temperature on Monday is -13°C.
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Pre-Assessment
Subtracting Integers with Counters
Student Activity Handout
Name: ___________________________
Date: ____________________________
34
Link: http://www.nearnorthschools.ca/it/PRISMNEO/list.asp?concept=All&grade=7
Instructions: Complete the following handout using the learning object titled “Subtracting Integers with Counters”.
Complete Parts A and B and answer all questions. Good luck!
Part A
How the Zero Tool Can Help You! & Using the Model
•
•
•
•
Click on “How the Zero Tool Can Help You” on the main menu page
Explore the zero tool with your partner
Once finished, explore “Preparing to Use the Model” and “Creating the Model” (select tabs 3 and 4) with your
partner and follow all instructions on the screen
Answer the following questions
QUESTIONS:
1. Represent the following integers by drawing positive and/or negative counters. (4 marks)
a) 3
b) -2
c) -4
d) 0
2. Use “zero counters” to create different models for the integers in question 1. (4 marks)
a) 3
b) -2
c) -4
d) 0
3. What are some real-life situations that use the subtraction of both positive and negative integers? (2 marks)
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Handout
Page 1 of 4
Subtracting Integers with Counters
Student Activity Handout
Name: ___________________________
Date: ____________________________
Subtracting Integers
•
•
•
•
•
Explore the following with your partner:
o “Subtracting Integers” (tab 5)
o “Subtracting Integers Using the Zero Model” (tab 6)
o “Just a Little More Practice” (tab 7)
Follow all instructions on each screen
Practice at least 5 questions on all three tabs
Make sure to select Show Instructions on the “Just a Little More Practice” page
Once you’ve practiced, answer the questions below
QUESTIONS:
1. Solve each of the following subtraction problems by drawing coloured counters. Use the zero tool and cross out
the counters you wish to “take away” to arrive at your answer. (8 marks)
a) 4 - 3 = _____
b) 3 - (-1) = _____
c) (- 1) - (- 5) = _____
d) (- 4) - 8 = _____
Comparing Subtracting and Adding
•
•
•
Click on the “8” tab at the bottom of the screen
Follow the instructions on the screen, making sure to explore at least
3 questions (pay attention to the subtraction AND addition questions)
Answer the questions below
QUESTIONS:
1. Using one of the questions you explored on the screen, write each subtraction and addition equation below. (2
marks)
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Handout
Page 2 of 4
Subtracting Integers with Counters
Student Activity Handout
Name: ___________________________
Date: ____________________________
2. Show how the subtraction model using the zero tool can also be used for the addition of integers using the
equations you recorded for question 1. Explain your answer. (3 marks)
Practice – Using Counters
•
•
•
•
•
Click on the “9” tab at the bottom of the screen
Take turns with your partner to see who can get the most questions
correct out of 5 questions each
Follow the instructions on the screen
Press “New Question” to start a new question
Fill in the required information below. Good luck!
Record your questions and answers in each column of the table below. (5 marks)
Names
Q1
Q2
Q3
Q4
Q5
WINNER’S NAME: ____________________________
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Handout
Page 3 of 4
Score
(out of 5)
Subtracting Integers with Counters
Student Activity Handout
Name: ___________________________
Date: ____________________________
Part B
Answer the following questions.
1. If two integers are positive, is their difference always positive? Show an example. (1 mark)
2. If two integers are negative, is their difference always negative? Show an example. (1 mark)
3. Create a subtraction problem with a answer equal to zero. (1 mark)
4. The temperature was -8°C on Friday. On Monday, the thermometer dropped 5 degrees from Friday’s temperature.
Use the zero tool and positive and negative counters to show the change in temperature. (3 marks)
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Handout
Page 4 of 4
Subtracting Integers with Counters
Name: Answer Key for Teacher
Student Activity Handout Answer Key
34
Link: http://www.nearnorthschools.ca/it/PRISMNEO/list.asp?concept=All&grade=7
Instructions: Complete the following handout using the learning object titled “Subtracting Integers with Counters”.
Complete Parts A and B and answer all questions. Good luck!
Part A
How the Zero Tool Can Help You! & Using the Model
•
•
•
•
Click on “How the Zero Tool Can Help You” on the main menu page
Explore the zero tool with your partner
Once finished, explore “Preparing to Use the Model” and “Creating the Model” (select tabs 3 and 4) with your
partner and follow all instructions on the screen
Answer the following questions
QUESTIONS:
1. Represent the following integers by drawing positive and/or negative counters. (4 marks)
a) 3
b) -2
c) -4
= negative
= positive
d) 0
2. Use “zero counters” to create different models for the integers in question 1. (4 marks) – answers may vary
a) 3
b) -2
c) -4
d) 0
3. What are some real-life situations that use the subtraction of both positive and negative integers? (2 marks)
- temperature dropping
- stock market dropping
- spending more money than what you have, etc.
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Handout Answer Key
Page 1 of 4
Subtracting Integers with Counters
Name: Answer Key for Teacher
Student Activity Handout Answer Key
Subtracting Integers
•
•
•
•
•
Explore the following with your partner:
o “Subtracting Integers” (tab 5)
o “Subtracting Integers Using the Zero Model” (tab 6)
o “Just a Little More Practice” (tab 7)
Follow all instructions on each screen
Practice at least 5 questions on all three tabs
Make sure to select Show Instructions on the “Just a Little More Practice” page
Once you’ve practiced, answer the questions below
QUESTIONS:
1. Solve each of the following subtraction problems by drawing coloured counters. Use the zero tool and cross out
the counters you wish to “take away” to arrive at your answer. (8 marks)
a) 4 - 3 = __1__
b) 3 - (-1) = __4__
c) (- 1) - (- 5) = _4___
d) (- 4) - 8 = __-12__
Comparing Subtracting and Adding
•
•
•
Click on the “8” tab at the bottom of the screen
Follow the instructions on the screen, making sure to explore at least
3 questions (pay attention to the subtraction AND addition questions)
Answer the questions below
QUESTIONS:
1. Using one of the questions you explored on the screen, write each subtraction and addition equation below. (2
marks) – sample answer
(-4) – (+9) = -13
(-4) + (-9) = -13
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Handout Answer Key
Page 2 of 4
Subtracting Integers with Counters
Name: Answer Key for Teacher
Student Activity Handout Answer Key
2. Show how the subtraction model using the zero tool can also be used for the addition of integers using the
equations you recorded for question 1. Explain your answer. (3 marks) – 1 mark for each set of counters, 1 mark
for explanation
(-4) – (+9) = -13
(-4) + (-9) = -13
This model works for both because
subtracting a positive integer is the
same as adding a negative integer of
equal value.
Practice – Using Counters
•
•
•
•
•
Click on the “9” tab at the bottom of the screen
Take turns with your partner to see who can get the most questions
correct out of 5 questions each
Follow the instructions on the screen
Press “New Question” to start a new question
Fill in the required information below. Good luck!
Record your questions and answers in each column of the table below. (5 marks) – sample answer
Names
Q1
Q2
Q3
Q4
Q5
Score
(out of 5)
John
1 - 5 = -4
(-3) - 2 = -5
(-2) - (-3) = 1
8 - (-9) = 17
4 - (-7) = 11
4
Jane
8-5=3
(-4) - (-5) = 1
1 - (-3) = 4
9 - (-3) = 12
(-6) - 4 = -10
5
WINNER’S NAME: _______Jane____________
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Handout Answer Key
Page 3 of 4
Subtracting Integers with Counters
Name: Answer Key for Teacher
Student Activity Handout Answer Key
Part B
Answer the following questions.
1. If two integers are positive, is their difference always positive? Show an example. (1 mark)
No, it depends on whether or not the first number is larger or smaller than the second number in the
equation.
E.g. 2 - 3 = -1 vs. 3 - 2 = 1
2. If two integers are negative, is their difference always negative? Show an example. (1 mark)
No, it depends on whether or not the first number is larger or smaller than the second number in the
equation.
E.g. (-2) – (-3) = 1 vs. (-3) – (-2) = -1
3. Create a subtraction problem with an answer equal to zero. (1 mark)
2–2=0
4. The temperature was -8°C on Friday. On Monday, the thermometer dropped 5 degrees from Friday’s temperature.
Use the zero tool and positive and negative counters to show the change in temperature. (3 marks)
= negative
(-8) - 5 = -13
= positive
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Handout Answer Key
Page 4 of 4
Subtracting Integers with Counters
Name: ___________________________
Birthday: ____________________________
Student Activity Post-Assessment
6
Instructions: Answer the following questions to the best of your ability. You are not permitted to use a calculator.
Good luck!
1. Solve the following subtraction problems. (4 marks)
a) 6 - (- 4)
b) (- 3) - (- 5)
c) (- 7) - 6
d) 6 - (- 11)
2. The temperature was -18°C on Friday. On Monday, the temperature dropped 8 degrees from Friday’s. Calculate
the difference in temperature. (2 marks)
Subtracting Integers with Counters
Student Activity Post-Assessment
Name: ___________________________
Birthday: ____________________________
6
Instructions: Answer the following questions to the best of your ability. You are not permitted to use a calculator.
Good luck!
1. Solve the following subtraction problems. (4 marks)
a) 6 - (- 4)
b) (- 3) - (- 5)
c) (- 7) - 6
d) 6 - (- 11)
2. The temperature was -18°C on Friday. On Monday, the temperature dropped 8 degrees from Friday’s. Calculate
the difference in temperature. (2 marks)
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Post-Assessment
Subtracting Integers with Counters
Student Activity Post-Assessment
Answer Key
Name: ___________________________
Birthday: ____________________________
6
Instructions: Answer the following questions to the best of your ability. You are not permitted to use a calculator.
Good luck!
1. Solve the following subtraction problems. (4 marks)
a) 6 - (- 4)
b) (- 3) - (- 5)
c) (- 7) - 6
d) 6 - (- 11)
= 10
=2
= -13
= 17
2. The temperature was -18°C on Friday. On Monday, the temperature dropped 8 degrees from Friday’s. Calculate
the difference in temperature. (2 marks)
(-18) - 8 = -26
The temperature on Monday is -26°C.
© 2007 University of Ontario Institute of Technology (UOIT) ~ Permission to Copy
Teacher-Created Resources: Student Activity Post-Assessment