Adding Machine 2.0

Purpose:  

• Identify patterns on a hundred chart
• Develop fluency in adding/subtracting by 9s and 11s (near 10s)

Number of Players:  2

Objective:  Be the first player to reach or exceed 120.

Materials

• 120 Chart
• 2 game tokens (small Legos, coins, beads, etc.)
• 6 sided block with the numbers:  +9, +9, -9, +11, +11, -11 or
• spinner from Wheeldecide.com labelled: +9, +9, -9, +11, +11, -11

How to Play:

• Start on the number 45.
• Player 1 rolls the dice/spinner and moves their game token by following the instructions on the dice/spinner.
• Player 2 rolls the dice/spinner and moves their game token by following the instructions on the dice/spinner.
• Players may not go below 1.  If players rolls less than 1, they just stay at 1.
• Players continue rolling and moving their game until a player reaches/exceeds 120.

What to watch for:

In the beginning, students may want to count out each square on the hundred chart.

As students become more comfortable, they will notice that there is a pattern.  They can add 10 and then add 1 to get to 11 or subtract 1 to get to 9.  Watch when they subtract that when they subtract 10, that they then subtract 1 more to get to 11 and add 1 to get to 9.  This is not intuitive in the beginning.

Edit