Subtraction – Fingers II
Two methods
Subtraction can be thought of as ‘take away’ or ‘difference.’ Both models are essential to a complete understanding of subtraction. Have your students practice both ways of thinking of subtraction using these finger subtraction methods.
We’ll use 11- 3 for our examples.
Take Away (on the left): Start with a closed fist and say ‘11.’ Then, lifting one more finger each time, count ‘10, 9, 8.’ When your student sees 3 fingers raised, the counting stops. You now have the result that taking 3 away from 11 leaves 8.
Difference (on the right): This uses ‘counting on,’ much as we did for Easy Way Finger Addition. What we are doing is finding out which number we need to add to 3 to get 11.
Have your student make a closed fist and say ‘3.’ Then, lifting one more finger each time, count ‘4, 5, 6, 7, 8, 9, 10, 11.’ When your student says ‘11,’ there are 8 fingers raised– the difference between 3 and 11 is 8.
