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The ideas in this fraction lesson are taken from Math Mammoth Fractions 1 book. Only a few examples of each problem type are shown; you should make more problems of each kind for the student.

 Adding and subtracting unlike fractions
Free lesson plan from HomeschoolMath.net

Cover the page below the black line. Then, try to figure out additions below. Manipulatives may help.

+ = 1 3 + 1 2 = What fraction  would this be?

+ = 1 3 + 1 4 = What fraction  would this be?

Did you solve the problems above? Study the pictures below for solutions. Discuss with your teacher. 

+ 1 3 + 1 2     ↓   ↓     + = 2 6 + 3 6 = 5 6

+ 1 3 + 1 4     ↓   ↓     + = 4 12 + 3 12 = 7 12

1. Write the fractions. Convert them into equivalent fractions. Add. Color parts where needed.

+       +           ↓   ↓       + = a.     +     =

Let's write the addition all on the same line now (horizontally).   + = + =   3 10 + 2 5 = 3 10 + 4 10 =      10

2. Change to equivalent fractions first, and then add. Each box below has TWO problems. In the bottom problem, you need to figure out what kind of pieces to use, but the top problem will help!

a. + = + =   1 2 + 1 6 =      6 + 1 6   = + = + =     + = + =
c. + = + =     +   =   +   = + = + =     + = + =

3. Look at the problems above in exercise (2). What kind of parts did the fractions have? What kind of parts did you use in the final addition? Fill in the table.

4.  Split the parts     so that both     fractions will have     the same kind of parts.     Write an addition sentence.

These pictures change into...   ...these.   Example:          1 4  +  3 8   2 8  +  3 8  =  5 8

a.     +     =
d.     +     =

5. Fill in the table based on the problems above in exercise (4).

6. Now think: How can you know into what kind of parts to convert the fractions that you are adding? Can you see any patterns or rules in the table?
 

7. If you think you know what kind of parts to convert the fractions to, try these problems. Don't worry if you don't know how to do them - we will study this more in the next lesson.

Next lesson: Adding unlike fractions 2: finding the common denominator

The ideas in this fraction lesson are taken from the Fractions 1 book. Only a few examples of each problem type are shown; you should make more problems of each kind for the student.

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