This is a complete lesson for first grade about the connection between addition and subtraction. It contains the instruction for the student and lots of exercises. Students write matching addition and subtraction "sentences" or equations, first using a visual model. Then, they are given the addition equation and they write the corresponding subtraction equation and draw a picture. Similarly, they then write a matching addition for a given subtraction equation. The lesson also contains a puzzle problem about comparing the values of addition and subtraction equations.

 How many colored circles? How many white ones?          4    +    6     = 10       3    +    4     = 7 Cover the colored circles. Write a subtraction sentence.          10 −    4    =    6 Cover the colored circles.       7 −    3    =    4

1. Make an addition sentence and a subtraction sentence from the same picture.

 a.       ______ + ______ = ______ 7  − ______ = ______ b. ______ + ______ = ______ 6  − ______ = ______ c.     ______ + ______ = ______ 5  − ______ = ______ d. ______ + ______ = ______ 6  − ______ = ______ e. ______ + ______ = ______ 8  − ______ = ______ f. ______ + ______ = ______ 6  − ______ = ______

2. Make an addition sentence and a subtraction sentence for the same picture.

 a.         ______ + ______ = ______

______ − ______ = ______

 b. ______ + ______ = ______

______ − ______ = ______

 c. ______ + ______ = ______

______ − ______ = ______

 d. ______ + ______ = ______

______ − ______ = ______

3. In each problem, draw circles and then color some circles to fit the addition
sentence. Then cover the COLORED circles and make a subtraction sentence.

 a.    7  +  1  = ______ ______ − ______ = ______ b.     6  +  3  = ______ ______ − ______ = ______ c.    2  +  3  = ______ ______ − ______ = ______ d.    2  +  5  = ______ ______ − ______ = ______ e.   7  +  4  = ______ ______ − ______ = ______ f.   3  +  3  = ______   ______ − ______ = ______

4. Cover the colored objects, and write a subtraction sentence to fit the picture.

 a.          ______ − ______ = ______

 b. ______ − ______ = ______

c. ______ − ______ = ______

d. ______ − ______ = ______

e.     ______ − ______ = ______

f. ______ − ______ = ______

 g.           ______ − ______ = ______

 h. ______ − ______ = ______

5. In each problem, draw some circles and color some circles to fit the addition
sentence. Then cover the COLORED circles and make a subtraction sentence.

 a.    9  +  1  = ______ ______ − ______ = ______ b.    7  +  2  = ______   ______ − ______ = ______ c.    10  +  4  = ___   ______ − ______ = ______ d.    10  +  2  = ___   ______ − ______ = ______

6. Draw circles to fit the subtraction sentence. Write an addition sentence, too.

 a.    9  −  4  = ___ ______ + ______ = ______ b.   10  −  5  = ___  ______ + ______ = ______ c.   8  −  5  = ___ ______ + ______ = ______ d.   8  −  4  = ___ ______ + ______ = ______ e.   7  −  4  = ___ ______ + ______ = ______ f.   9  −  8  = ___ ______ + ______ = ______ Subtract or add. Do not write the answers; just solve them
in your mind. Then compare, and write  <  ,  > ,  or  = .

 3 3 − 1 9 − 7 8 − 7 5 + 2 8 + 2 10 − 2 8 − 2
 6 + 5 6 6 − 4 2 + 3 10 − 1 10 − 3 10 + 0 10 − 0
 10 10 − 1 8 − 5 5 + 3 7 − 4 8 − 5 8 − 1 8 + 1

This lesson is taken from Maria Miller's book Math Mammoth Subtraction 1, and posted at www.HomeschoolMath.net with permission from the author. Copyright © Maria Miller. The lesson addresses the following Common Core standard for 1st grade: 1.OA.6.

#### Math Mammoth Subtraction 1

A self-teaching worktext for 1st grade that covers subtraction concept, fact families, difference, memorizing basic facts, and lots of word problems.