Let's Make a Game of It
The activities below can be done alone or in a group. Most can be played competitively. See MATH GAMES
for ideas on how to use math activities competitively.
A Simple Subtraction Game
Take a random double digit number like "85" and use it as a starting point. (You might use a number that has meaning as well, like the last two digits of your phone number, or the age of a favorite aunt, etc.)
Use the student's age, and repeatedly subtract from the starting number. For example: 85 - 8 = 77; 77 - 8 = 69; 69 - 8 - 61; 61 - 8 = 53; etc.
This subtraction game can be played in the car, can be played alone or competitively. Change the subtrahend and subtractor. See below for more subtraction games and activities.
Demonstrate Simple Subtraction
Children often use the term "take away" rather than "subtract" when they first start solving subtraction problems. It is an easy concept to understand.
Pre-requisite: Student can correctly add one digit numbers.
Supplies Needed: Counters or other tangible objects (paper clips, crayons, spoons, etc.)
- Put six objects in front of the child.
- Ask them to take two objects away.
- Ask how many are left.
- Say, "Yes, 6 - 2 = 4."
- Show them the math equation on a flash card of paper.
- Next time show them the equation first.
- Say, "We read this as "five minus three."
- Have the student read the equation.
- Put the number of objects in front of the student.
- Ask them to take away the correct number.
- Repeat with four of five different equations.
What is Missing?
When students realize that subtraction is the reverse of addition, they will learn the subtraction facts much quicker.
Supplies needed: Digits (refridgerator magnets, index cards with the digits written on them, etc.)
You will also need a "plus" sign and "equal" sign.
Second and Subsequent Sessions
- With the digits, lay out the equation "4 + 1 = 5."
- Ask the student to read it.
- Take the 1 digit away.
- Ask, "What number should go here?"
- With the next equation, do not show them the complete equation first.
- Set the equation up as follows: "3 + __ = 7."
- Ask, "What number would make this equation correct."
- Affirm their correct answers.
- Repeat with four or five different equations.
- This subtraction activity will be added to the next time you do it.(Right Below)
- Set up a simple addition equation as you did before, with one digit missing. Example: "2 + __ = 6."
- Ask, "What number would make this equation correct."
- When they answer "four," respond with, "Yes, you are right. 2 + 4 = 6 , AND 6 - 4 = 2"
Learning Subtraction Facts
In addition to understanding subtraction concepts, students also need to "know" the simple subtraction facts. Here is our recommendation for the order of learning this.
Subtract By One
This is easy to learn. Learn all the subtraction by one facts. It is simply counting backwards by one. (10 - 1; 9 - 1; 8 - 1; etc.)
Subtract By Two
Subtracting by two is a little harder.
They should learn all these math facts (10 - 2; 9 - 2; 8 - 2; etc.)
Flash Card Review
Keep a stack of the subtraction facts they have learned for a quick "flash review." Add to the stack as they learn other equations.
To start, you will have the subtraction facts by one, then add the subtraction facts by two.
Some children may learn entire groups at once, or they may only learn one a day. There is no reason to go to quick. Remember, when your child graduates from high school it will not matter whether it took him one month or six months to learn the basic subtraction facts. Comprehension is the key.
Flash cards can be homemade or purchased.
Hundreds of Worksheets - Only $5.99
Your K to 3rd grader can practice subtraction facts, as well as addition, multiplication, and division - with over 900 pages from www.A-to-Z-worksheets.com.
Other Ways to Review
Other methods for reviewing subtraction facts include:
- Computer games
- Wrap Ups
More Activities to Comprehend Subtraction
The student has learned that subtact means to "take away." This is a basic method of understanding subtraction.
The next set of subtraction games and activities provides other hands-on projects which help them grasp the concept of subtraction. These should be done one at a time, during the weeks and months the student is learning the basic subtraction facts.
Subtracting with Cuisennaire Rods
Supplies needed: Individual set of Cuisennaire Rods. These manipulatives are one of the best (if not the
best) for teaching addition and multiplication
See below if you do not have access to these blocks.
Second and subseqeuent Sessions
- Use the rods to demonstrate this equation
- Set the 6 rod on the table. To the side of it, the 4 rod and 2 rod should be lengthwise ("choo choo train style.")
- Say, "This shows that "4 + 2 = 6; and that 6 - 4 = 2."
- Take the 4 rod and 2 rod away. Leave the 6 rod in place. Put a 3 rod along side the 6 rod.
- Ask, "6 - 3 = what?"
- Repeat with several simple subtraction equations.
- Give them the 6 rod.
- Ask them to find all the subtraction facts with 6. (6 - 1 = 5; 6 - 2 = 4; 6 - 3 = 3)
- At different sessions, use different rods (10, 9, 8, 7, 6, 5)
The first activity above with the counters demonstrated that subtraction is "taking away." This demonstrates that subtraction is breaking apart a whole.
By using different manipulatives, you have shown them to view subtraction as taking a certain number away (ie.subtraction by two's); and parts of a whole (subtraction from 6.)
Number Line Subtraction Games - Basic
Game boards where students count ahead on spaces on the board demonstrate addition. In the same way, counting spaces backwards demonstrates subtraction (go back three spaces.)
This is a more abstract concept than adding and subtracting concrete items like paper clips or counting bears. The relationship of the numbers to each other becomes apparent to the student.
You will need a number line for this game. Here are some ideas:
- Make a number line on blank paper. Use a ruler to draw a "ladder" with spaces that are 2 cm X 2 cm (large enough for a market to sit on). Number the spaces, starting at "0."
- Use a ruler with numbers already marked.
- Use a Hundreds Board
- Mark up an old game board that has spaces moving from one end of the board to another. Number the spaces from "0" on.
- Use kitchen or hallway tiles which form squares as a number line. Instead of using the marker to move alone the space, the child can be the human marker.
A Little Harder
- Start at the ten
- Roll the dice, move that many spaces backwards.
- Continue until you get to 0. You need an exact number.
- Start at ten.
- Roll the dice.
- You may NOT count. You must state the subtraction fact, and move if you get it right: (ie 10 - 3 = 7. Move to 7.)
If you used a math balance to teach addition, it can also be used for subtraction games.
- Place the digits in a box.
- Reach in and pull out any two, without looking at the digits.
- Put the larger number on the left hand side of the balance.
- Put the smaller number of the right hand side of the balance.
- The student needs to mentally calculate the difference between the two numbers, and verbally announce it.
- The digit they called out is placed on the right hand side of the balance.
- If they were correct, the two sides will balance.
Two Digit Subtraction
Using Cuisennaire Rods with Larger Subtraction Facts
Now we come to equations where the minuend (ie the first number - or largest number in elementary math) is greater than 10.
Examples: 13 - 6; 17 - 9; 12 - 5 etc.
With these equations, the Cuisennaire Rods are particularly effective.
Let's look at an easy example: 13 - 9
- Make "13" by laying the 10 rod and the 3 rod lengthwise ("choo choo train style.")
- Lay the 9 rod next to the 10 rod, so they are lined up at the bottom.
- Ask the child, "What rod do I need to add to the 9 to make 13?"
- The child can easily see that the missing rod needs to be one larger centimeter larger than the 3 rod.
- To make this a game, leave the ten rod on the table.
- Blindly draw two other rods. Put them in place of the 9 and 3 rods in the example above.
- The child has to announce the answer. Then, he or she gets the correct rod to see if the answer is correct.
Hundred Board Subtraction
This is another fantastic way to demonstrate the relationship of the numbers to each other.
Need: A 100 Board with numbers written in the spaces, and two markers. (The transparent markers are ideal, but not essential.)
Subtraction By Nine
The Hundred Board can be used to teach subtraction with the larger numbers as the subtrahend (ie the number you subtract by
- Put the marker on any space above ten on the Hundred Board. For example, we will put it on 25.
- Ask, "What is 25 - 10?" The student should answer "15" and you point to the 15 space.
- Ask, "If 25 - 10 is 15, what is 25 - 9?"
- The first few times, the student may need to count backwards to get to the correct space.
- Allow them to count backwards as many times as they need to, but help them "see" that their final answer is always one more than the difference from ten.
- As they progress in this exercise, make it a little more challenging:
- Do not allow them to count backwards. They have to look at the board and announce the answer.
- As they get more confident, allow them to look at the board but do not put a marker on the starting space.
- Take the board away so they can not see the spaces, and tell the answer.
Subtraction By Eight and Seven
After the student is able to subtract by nine using the Hundreds Board game listed above, use it to teach subtraction by the other numbers.
- Repeat the subtraction game above using eight instead of nine as the subtrahend.
- Continue using the Hundred Board for your subtraction games as you learn subtraction by seven and smaller numbers.
Two Digit Subtraction
Now we are ready to subtract larger numbers over 10.
Base Ten Blocks
The Base Ten Blocks are one of the best manipulatives to teach subtraction with place value to the tens, hundreds, and thousands. If you do not have the Base Ten Blocks, there are a few alternatives you can make.
Start with subtraction games and activities without regrouping.
- For our example, we will subtract 43 - 21.
- Show the student the problem.
- Ask them to use the blocks to represent 43. They should set out four 10 blocks and 5 unit (one) blocks.
- Make sure you arrange the blocks with the tens to the left and units to the right, as they would see the equation in a math problem.
- Ask them to take away 21. They should remove two 10 blocks and 1 unit block.
- Ask them what is left (22.)
- Show them how to work the problem out on paper.
- Repeat with four or five other problems.
This activity is fairly straight forward, and many students will grasp the concept with just one or two sessions using this activity.
It does prepare them for the next activity (subtraction with regrouping) which may take longer to master.
Let's start with a problem that requires regrouping.
- Our example is 52 - 17.
- Show them the problem
- Have them set out the blocks to represent 52 (five 10 blocks, 2 unit blocks)
- Ask them to take away the 7 units (ones) first.
- When they are unable to, see if they can come up with any ideas of what to do on their own.
- If they do not suggest it, demonstrate that they could give you a ten block in exchange for ten unit blocks.
- Make the exchange.
- Now have them take away seven units and one ten (17).
- Look at the problem on paper. Tell them you are going to solve it both on paper and with the blocks.
- Start at the beginning - with five 10 blocks and two unit blocks.
- When you make the exchange, show on paper how you reduce the 5 to a 4, and change the 2 to a 12.
- Solve the problem again.
- Repeat the steps with two more problems.
This equation is a little taxing to many young minds. It is recommended that you do only two or three of these problems at one sitting; but continue with this activity on a regular basis until they master the concept.
Again, be patient. They will grasp it. Doing this many times with a few problems is more productive than doing it a few times with lots of problems.
Hundred Board Subtraction Jump
One of the most effective subtaction games to practice double digit subtraction is the Hundred Board Subtraction Jump.
- Hundred Board with numbers written on the spaces
- Marker for each player
- Two dice (10 digit dice are ideal, but the regular 6 digit dice are also usable.)
This game takes about 15 to 20 minutes to play. It is a game you may wish to play once every one to two weeks until subtraction becomes easy to your students.
- Both players start with their marker at 100.
- Hold each dice in one hand. Roll them out of the hand to land so one is to the left and one is to the right.
- "Read" the dice you would a number on paper. The dice to the left hand is the ten place value and the die to the right is the unit place value. A two and three would read "23."
- The player looks at the board, calculates the difference between the space their marker is on and the two digit number rolled from the dice. They move their marker to that number.
- Example, the player is on 100. They roll 23. 100 - 23 = 77. They move to 77.
- If a player gets an incorrect answer, he or she returns to the space they were on previous to this turn.
In addition to practicing subtraction, this game helps them estimate answers. This skill will be invaluable on timed tests later.
Subtraction With Three and Four Digit Numbers
Base Ten Blocks
As students master double digit problems, you can begin subtraction games with three and four digits.
Continue the subtraction games above for the Base Ten Blocks. However, now you will start with place value to the hundreds. You will follow the same steps above, but use the hundreds block from the Base Ten Blocks as well.
When appropriate, add place value to the thousands as well. You will need the one thousand cube.
If you choose not to buy the thousand cubes, show the child a picture. Explain it would be ten of the Ten Blocks stacked on top of each other. You can draw a picture of a cube, make a cube our of paper, or use small boxes to represent thousands.
Money is an ideal way to practice subtraction. It also happens to be very beneficial, because children are quite interested in obtaining things for themselves. Knowing how much they have to spend, and how they will have left is a natural motivator.
Supplies Needed: One dollar bills and coins (play money or real can be used. Some families use a handful of change and make $1 and $10 bills out of paper.) Also use a toy catalog, shopping brochure, grocery advertisement, etc.
- Give the child $10
- They choose an item to "purchase."
- Then they must subtact the purchase price from their $10.00
- After they have done the problem on paper, repeat it with the money and change.
- Determine if they did the problems correctly.
Now that your student has learned to add and subtraction, it is time to start one of life's most important subtraction games - budgeting!
Would you agree life seems to "take away" the money more quickly than it "adds" it to your bank account?
Keeping a budget is an important step in learning the value of money, as well as practicing addition AND subtraction simultaenously.