• building conceptual understanding
  • Pizza Fractions – Unit Fractions

    I always start with this activity as a foundation for comparing unit fractions. Every year, this activity is a huge hit with my students!

    Fraction Pizza Activity: Team Challenge

    Group students into groups of 4 and put the timer on for 30 minutes.
    1) Work with your group to make pizzas
    2) Everyone will be assigned a fraction: 1/2, 1/3, 1/4, 1/6
    3) Make sure you cut your pizza into equal parts
    4) Decorate and come up with a creative pizza store name!

    The most crucial part of this activity comes through the discussion.
    After the time has ended, allow the students to discuss and work together to order the unit fractions from largest to smallest. “Take one piece of each pizza and order the size from largest to smallest”

    Team discussion questions
    1) What do you notice about the denominator and the size of the pizza?
    2) How do you connect this to your knowledge of pizzas?
    3) What did you learn?

    A unit fraction is one piece of the fraction.
    In unit fractions, the bigger the denominator, the smaller the piece.

    This is because a fraction is part of a whole. The denominator tells you how many equal pieces you need to cut the whole. The larger the denominator, the more you have to cut the whole, which makes the pieces smaller.

    Practice using Fraction Bars

    Pair students up and give each pair a set of fraction bars. Allow students to compare unit fractions and come up with the explanation of WHY one fraction is larger than the other.

    Sentence Stem: “I would rather have …. because …. “

    “Stacking” the fraction bars, students will see that 1/3 is larger than 1/5.

    I would rather have 1/3 because in a unit fraction, the bigger the denominator, the smaller the piece! Thirds are larger than fifths.

    Practice using Number Lines

    After allowing students to get practice using fraction bars, we move into drawing number lines.(something they should already be familiar with!) The denominator tells you how many total equal parts of a whole — connect this to how many total parts students need to draw on their number line!

    When students draw out their number lines, point out that both number lines need to start and end at the exact point.

    I would rather have 1/4 because in a unit fraction, the bigger the denominator, the smaller the piece! Fourths are larger than sevenths.


    Student Examples
    I have found that making students prove their conclusion with a picture and with a sentence, has helped their understanding of fractions and helped boost their confidence with fractions! This also helped build a strong foundation for everything else that was to come with fractions in our unit.

    This is a part of our fraction series. Check out these other blogposts for more!
    – http://mustardseedteaching.com/fractions-introduction/
    – http://mustardseedteaching.com/comparing-fractions-with-common-denominators-common-numerators/
    – http://mustardseedteaching.com/making-half/

    What things do you do to help students build a good foundation of unit fractions?