Number Thief



by Stacey McKay

Current job is Computer Coordinator and Fifth Grade Teacher at Murdock Elementary School.

Instructional Objective Students will utilize problem solving strategies to formulate and adapt mathematical equations.


Learners/Context The learners are fifth grade students currently enrolled at Murdock Elementary. This game is to be utilized by students who complete their class work early. In order to accommodate the needs of all learners, the game is flexible in both game duration and difficulty.


Rationale Important skills for students to develop and reinforce are problem solving, critical thinking, and creativity. All of these skills can be taught but diminish when not frequently utilized.

A card game can be used to practice and reinforce these skills. The students begin by building basic mathematical equations. As their familiarity with mathematical equations expand, they can manipulate existing equations. Due to the flexibility of the game, learners will enhance creativity through the manipulation of mathematical symbols and develop critical thinking through the unlimited playing opportunities.


Process The game will be introduced and taught by the teacher during one class period. After students have demonstrated an understanding of the game, they will be allowed to play the game whenever they have free time. As their mathematical knowledge increases, they will be allowed to choose the level of difficulty and additional options.


Rules This number game is played is played like rummy. Follow the directions below:

1. First choose a dealer by having each player choose a card from the shuffled deck. The player with the highest card is the dealer and the player who begins the game. The dealer should deal 10 cards to each player. The remaining cards are placed face down to form the pickup pile . One card is turned over to form the discard pile.

2. The dealer begins by either choosing a card from the discard pile or the pickup pile. S/he attempts to combine digits with mathematical symbols to make an equation. If an equation is made it is placed face up on the table.

3. A player may "steal" another players equation by extending an opponents equation. Any combination of letters or symbols may be used. If an equation is stolen it is placed with any other equations that the "thief" may have.

4. After the player has placed any possible equations on the table, s/he must discard one card.

5. The player to the left continues the game in the same manner as the dealer began.

6. The play continues until one of the players runs out of cards. Scoring is determined by adding up all the cards that are forming equations. Each card is awarded it's face value and mathematical symbols are valued at 10. Any players with cards in their hand must subtract those cards from their total.

7. There are two wild cards, X and Y, which may represent any number or symbol. The player who uses a wild cards must identify its purpose. If a player has a wild card in his hand at the end of the game it is given a value of 10.

8. In the rare event that an equation is disputed, players should use a calculator to validate or invalidate the equation.

Optional Uses The game cards can also be used in other ways for instruction.

1. The math symbols can be changed from multiplication and division to either addition and subtraction or square root and exponents.

2. The scoring can remain the same except that players must add the value of the cards in their hand to the value of their equations on the table and the player with the lowest score wins.


Card Design


Design Process The game was designed to meet a specific problem. Students who finish their class work early needed a game or task that would be educationally sound, academically challenging and fun. The game can be easily adapted to any level of play while still reinforcing problem solving, critical thinking and creativity.

The game was piloted with four 5th grade students. Initially, the students were overwhelmed and confused by the rules until one student exclaimed, "Hey! It's just like rummy!" This told me that the rules needed to be written in a simpler language if the students are to learn the game without teacher intervention. As the game progressed, it became clear that there were not enough equal signs and that the symbol for multiplication and the wild card X were confusing. Once the game was in full motion, the kids had a great time. It appeared to easy for them having plus and minus signs in the deck. From these observations I made several changes. I tried to simplify the rules by using more familiar terms and identifying it as a rummy style game. To clarify the confusion between the X's the number or symbol name was written on the bottom of the cards. Finally, more equal signs were added to the deck. For this group of students, I would take out the plus and minus signs and add square root and exponents.