Math Background

Addition and Subtraction of Fractions: Tips and Tricks

  • Paper fraction kits are excellent, inexpensive manipulatives for teaching addition and subtraction of fractions. Begin by using several different colors of letter-size construction paper. You can use a white sheet of paper as the whole. Take a colored sheet and fold it in half. Tear or cut the paper down the crease. You now have two equal pieces. Each piece represents one of two equal parts or one half. If you lay the two halves on the white whole, the two halves will completely cover the white sheet of paper. Take a sheet of another color and fold it in half, then in half again. If you open the paper and cut along the creases, you will have four equal pieces. Each piece represents one of four equal parts, or one fourth. You can use other colors of paper to construct eighths and sixteenths by making additional folds of the paper. You can have students make these kits as a class project.
  • When using manipulatives to teach concepts about fractions, be sure that you and the students use the same colors to represent specific fractions. This will make instruction easier for students to follow. In other words, if your class is constructing student fraction kits out of construction paper, have all students use red for halves, blue for fourths, yellow for eighths, and green for sixteenths.
  • Include the terms numerator and denominator in vocabulary and spelling tests. This will allow students to become more familiar with the terms. Have students use the terms in both oral and written sentences.
  • Post a diagram in the classroom displaying numerator over denominator. This will provide students with reinforcement of the proper location of these terms.
  • Post a diagram in the classroom displaying examples of adding and subtracting fractions with like denominators, along with pictorial representations.
  • Have students write real-life examples of adding and subtracting fractions. This can be done in a math journal during this unit.

Houghton Mifflin Math Grade 3