Whole Numbers as Fractions: Math - Grade 3-4

Subject: Math

Grade: 3-4

Lesson Objective: Learning to write whole numbers as fractions

Common Core Standard: CCSS.Math.Content.4.NF.A.1 – Explain that equivalent fractions can be written with different numerators and denominators. Use visuals to explain that the number and size of parts can change while the whole number stays the same. With this in mind, recognize and create equivalent fractions.

Materials: Whole Numbers as Fractions Worksheet

Starter: 

Ask:

• "What are the top and bottom numbers on fractions?" (Allow students to answer and discuss the question. As appropriate, ask some of the follow-up questions.)
• "Which part is the numerator and denominator?" (Make sure students know the numerator is the top number and the denominator is the bottom number.)
• "What does the numerator represent?" (Make sure students know the numerator represents how many parts there are.)
• "What does the denominator represent?" (Make sure students know the denominator represents what size the parts are – how many parts make a whole).

Main: 

Say:

• "Sometimes working with fractions is easier than working with whole numbers."
• "We can write whole numbers as fractions. This is helpful when adding and subtracting fractions and whole numbers."
• "If you had 1 cookie and cut it into 2 equal pieces, what fraction of the cookie would each piece be?" (Draw a circle with a line through the middle for the students to see. Make sure they understand that each part of the cookie would be ½).
• "How many halves represent the whole cookie?" (Allow the students to see that 2 halves (2/2) are the same as one cookie.)
• "If I cut a pie in 4 equal pieces, what fraction is each piece?" (1/4; continue drawing circles on the board with lines to show the parts.)
• "How many pieces would I have if I cut three pies in fourths?" (12 pieces)
• "We can write this as a fraction by writing 12/4. The 12 pieces go on top, and four goes on the bottom because that tells us how many pieces make one whole."
• "If I buy 16/8 of a cake for a party, how much cake am I buying?" (Use pictures to help the students understand that 16/8 is two cakes, each cut in 8 pieces.)
• "If my friend eats 3/1 pancakes, how many pieces of pancake do they eat?" (3 pieces)
• "Because the denominator is 1, each piece is a whole pancake. How many pancakes does that mean my friend ate?" (3 pancakes)
• "If I have two whole pies, how can I write that as a fraction?" (2/1 because there are 2 pieces, and 1 piece makes a whole. Draw two circles and continue to draw lines sectioning the circles with the following questions."
• "What if I cut each pie in half? How would I write that as a fraction?" (4/2 because now there are 4 pieces, and it takes 2 pieces to make a whole.)
• "If I cut every piece in half again so that each pie has four pieces, how do I write what I have as a fraction?" (8/4 since there are now 8 pieces and it takes 4 of these size pieces to make a whole pie.) (Make sure the children understand that 2/1, 4/2, and 8/4 are all different fractions representing 2.)
• "Now, you are going to work on some problems to help you practice what we just learned."

Feedback: Ask students if they have questions from their worksheets. Allow students to share or demonstrate writing whole numbers as fractions.