Here’s a game that’s sure to get you into a gobbly good mood for Thanksgiving while reinforcing your knowledge of the order of mathematical operations at the very same time! All you need are the following items to get started:
- One 6-sided die
- A one-minute timer (a watch or kitchen timer works well)
- Pens or pencils
- Scratch paper for each player
This is a game for more than 2 players in grades 4 to 7 (Ideas for younger students are listed at the end of this activity…).
Let’s first review the rules for the order of operations in mathematical expressions:
- When using parentheses, do the operations within Parenthesis first.
- If Exponents are in the expression, they are performed next from left to right.
- Next, if there is any multiplication or division, Multiply or Divide from left to right
- Lastly, anything to Add or to Subtract is done next from left to right
PEMDAS is a mnemonic that might help you recall the order of operations! You might remember it better by thinking of the following statement:
Please Excuse My Dear Aunt Sally!
(……. Even though my Aunt Sally does make a fine Thanksgiving pie! Gobble-Gobble!… )
Here are some examples of correctly using PEMDAS. Notice without these rules of order of operations, it would be difficult to determine a correct result in each expression:
5 + (4 / 2) = 5 + 2 = 7
(5 + 4) / 2 = 9 / 2 = 4.5
(5 – 4) / 2 = 1.5
5 – 4 x 2 = 5 – 8 = -3
5 x 4 – 2 = 20 – 2 = 18
5 x 4 / 2 = 20 / 2 = 10
(5 x 4) / 2 = 20
5 x (4 – 2)2 = 5 x 22 = 5 x 4 = 20
(5 x 4)2 – 2 = 202 – 2 = 400 – 2 = 398
Now let’s play the game:
- The player who rolls the highest number on the die goes first. Let’s call this person Player 1. New games continue to the left of Player 1 in turn and so on.
- Each player draws 3 boxes on a piece of scratch paper.
- Player 1 rolls the die 3 times to obtain 3 values. Any numbers will do, including repeating numbers. Each player then writes each number from left to right into their boxes in numerical order from highest to lowest number. For example, if the Player 1 rolled a 5, 2, and a 4, then everyone would write the following numbers in each of their 3 boxes:
- Using these 3 numbers, Player 1 then secretly creates a mathematical expression on another scratch paper using PEMDAS rules with those numbers in the order in which they appear. Player 1 does NOT reveal this expression to the other players.
- For example; let’s say for the numbers 5, 4, and 2, the Player 1 secretly decides to create the expression: 5 + (4 / 2)
- Next, Player 1 reveals the ANSWER for this expression to the other players, (which is 7 because 5 + (4 / 2) = 5 + 2 = 7), but Player 1 does NOT reveal the expression that was used to obtain that answer.
- Set the timer to begin.
- The other players have one minute to correctly guess the mathematical expression that gave the answer 7.
- When time is up, and everyone’s mathematical expressions are compared, any player who did not correctly identify the expression is penalized by writing one letter from the word T-U-R-K-E-Y onto their scratch paper (starting in order with the letter T …).
- Continue a new game with the next player to start. Each time a new game ends, all players who didn’t guess the correct expression add another letter from the word TURKEY to their scratch paper. Each time the entire word TURKEY is spelled, that player is eliminated from the game.
- To be the last player (or more than one if there are ties) who hasn’t spelled out the entire word “TURKEY.” “Gobble-Gobble!”
Ideas for taking this game further:
- The 3 numbers can be used in any order to create an expression.
- Use 4 or more numbers to create mathematical expressions.
- Take turns to create an expression on paper and then ask others to guess what numbers are used within it: For example, use the numbers 8, 2, and 3 to solve the following expression: ___+ ___ x ___ = 14. (solution: 8 + 2 x 3)
- For younger students: play a different game with a die where each player tosses the die 3 times (or another number of times or another number of dice). Then they add the numbers on the die (or dice), and determine in each game the winner(s) as those to get closest to the number 10 without going over. For each game, the winner(s) of each game must explain how they used the dice numbers to get to the goal number. Every time a player wins a game, they write a letter from the word “TURKEY” starting with T. The ultimate winner(s) are the first to write the entire word “TURKEY” and to say “Gobble-Gobble!”