I'm Odd: You're Even Years 3 - 6

Summary Easy to state and easy to start this calculator game provides opportunity to explore what happens to odd and even numbers when they are combined using any of the four operations. One child chooses to be the winner if the final calculator screen is odd, the other if the final screen is even. Now, by only choosing from the digits 0 - 9 and the four basic operations, each player tries to force the final screen to give them the win. Suitable for threading. Materials One calculator per pair Digit cards or equivalent for 0 - 9 One Poly Plug per pair

Procedure Children can easily make digit cards by tearing up a piece of scrap paper. Alternatively they write 0 - 9 as a list on a piece of paper. Players choose whether they will win if an odd number is the last display or if an even number is the last display. Turn the calculator on. Player A presses + or - or x or ÷ followed by one of the digit cards, then presses =. This digit card is then turned over (or the number is crossed off the list). Turned over cards are not used again. Player B takes the calculator, and presses + or - or x or ÷ followed by one of the digit cards, then presses =. This digit card is then turned over or crossed off. Note: In the photo Player A pressed + 2 = to get 2 on the screen. Then Player B followed with x 5 =. Therefore the screen shows 10 so far and digits 2 and 5 have been used.

Content addition facts beyond 10 division multiplication odd & even numbers operations - whole number pattern interpretation pattern recognition recording - calculator subtraction times tables

The calculator returns to Player A who continues the process of operating on the display using one of the remaining digit cards. Play continues until the last card is turned over. If the last display number is odd, the odd player wins - if even, the even player wins. It doesn't matter who did the final calculation. If a player presses clear during the game or causes a display that is not a whole number, the round is over and the opponent gets the point. Note: Zero is used twice. Once in the very first action by Player A as the zero evident on the screen when the calculator is turned on and once when the 0 digit card is used. Extensions Play It With Plugs: Sometimes play the game with plugs instead of the calculator (although the calculator can be used for checking). In this version, which is designed to help children 'see' the properties of odd and even numbers the plugs must always be lined up in two rows. Children begin with the zero plugs in the centre. Player A says they are starting with + or - or x or ÷ followed by one of the digit cards, then completes that action with the plugs. Player B now says one of + or - or x or ÷ followed by one of the digit cards and follows with the action. Each player must line the plugs up in twos (or twos with one extra) to complete their turn. The game continues in this manner until the last card is used. What is the largest even, or odd, number that can appear on the final screen when playing this game? What is the smallest?

Nichola Brandon St. Benedict's Primary School, Narrabundah Year 4 Nichola used this activity over at least six sessions and comments: This activity assists students with problem solving strategies. When engaging in this activity students are thinking about the properties of the number and the cause and effect of operations used with certain numbers. The conversation happening in my room around this activity was that of little mathematicians! As students engaged in the activity, I wandered around making sure I had a discussion about the properties of the numbers with every student. I'm Odd You're Even highlighted those students with a sound number knowledge and those students who were in need of further development. After engaging in this activity for a few sessions over the two weeks, I was able to engage in a sophisticated discussion with some of my students about why they chose the operations they did to make sure the answer would most likely be in their favour. Nichola also prepared this worksheet to guide the children's recording. Thanks for sharing Nichola.

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