108 Addition and Subtraction Concepts
All Strung Out
A game designed to build the concept
of equal difference
Materials:
Q^ Number Cards (50–98)
Q (^) One Subtrahend Spinner (+2 or +1 or –1)
Q^ Paper clip and pencil
Q^ Number line (1–100) Note: If number line is not available, cut apart
the rows of a hundred chart and tape the ends together.
Q^ String (or ribbon or strips of paper), scissors
Directions:
- Shuffl e the number cards and place face-down in a pile. The
fi rst player draws a card. This number will be the minuend. - The fi rst player spins the spinner to fi nd the subtrahend for the
subtraction expression. This player cuts a piece of string that
shows the difference (distance between the minuend and the
subtrahend). The player moves the string two numbers to the
right (when using the +2 spinner) and describes the equal
difference equation using the term “is the same as.” For
example, 86 – 28 is the same as 88 – 30. - If the player accurately models and describes the equal
difference equation, the player keeps the string. - Players take turns drawing number cards, spinning, modeling,
and describing the equal difference expressions. - After each player has fi ve turns, all players line up their pieces
of string, and compare their total lengths. The winner is the
player with the most string.
Content Differentiation:
Moving Back: Use the +1 spinner (move string one number to the
right).
Moving Ahead: Use the –1 spinner (move string one number to the
left) or make your own spinner.