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Adding and subtracting like fractions
Free lesson with a video

In the video below (also available at my Youtube channel), I explain how you can teach adding and subtracting like fractions, first using visual models, coloring the crossing out parts, and then advancing into abstract problems. I also include missing addend problems.

The lesson below also explains the same ideas. It is taken from Math Mammoth Fractions 1 book.

Fractions that have the same denominator are called like fractions. Fractions that have a different denominator are called unlike fractions. Write the answers to the pictures. Check with your teacher. + = 1 4 + 2 4 =     1 4  and  2 4  are like fractions since they have the same denominator, 4. In other words, they are the same kind of parts - fourth parts.   + =   2 9 + 4 9 =     + = 3 8 + 5 8 =     = 1

Adding the same kind of parts is easy - just add the __________________.

 
1. Write the addition sentence and the answer. Give your final answer as a mixed number if possible. Shade parts in the answer picture.

+ =     a.
+ =     c.
+ =     e.

 
2. Shade parts and write an addition sentence for each problem.

a.  Shade  5 8 .  Shade another 7 8 .
c.  Shade  6 10 .  Shade another 7 10 .
e.  Shade  6 14 .  Shade another 6 14 .

3. Fill in the missing fractions. Write your answer as a mixed number if possible.

4. Shade parts and cross out parts, and write a subtraction sentence for each problem.

a.  Shade 1 5 8 .  Cross out  7 8 .
c.  Shade 1 5 10 .  Cross out 2 10 .
e.  Shade  10 14 .  Cross out  3 14 .
g.  Shade 2 1 4 .  Cross out 1 2 4 .

5. Subtract like fractions. The principle is the same as in adding: you just subtract the numerators.

6. Make your own fraction problems! Make two different problems for each answer. 

7. Add. Write a subtraction problem for each addition. Use mixed numbers when possible.

Next lesson: equivalent fractions

The ideas in this fraction lesson are taken from Math Mammoth Fractions 1 book.

Math Mammoth Fractions 1 $4.50 A self-teaching printable worktext that teaches fractions and their operations with visual models. You don't need to just memorize fraction rules blindly - learn and understand! The book covers fractions, mixed numbers, equivalent fractions, adding and subtracting like fractions and unlike fractions, adding and subtracting mixed numbers, comparing fractions, and finding a fractional part of a group.