Playdough Fractions

Adapted from Kristine Nannini (youngteacherlove.com)
Lesson by Samantha Baynton
quick lesson final

Curriculum 

Grade 1

  • Divide whole objects into parts and identify and describe through investigation, equal-sized parts of the whole, using fractional names (e.g., halves; fourths or quarters)

Grade 2

  • Determine, through investigation using concrete materials, the relationship between the number of fractional parts of a whole and the size of the fractional parts (e.g., a play dough circe divided into fourths has larger parts than a play dough circle divided into eighths)
  • Regroup fractional parts into wholes, using concrete materials (e.g., combine nine fourths to form two wholes and one fourth)
  • Compare fractions using concrete materials, without using standard fractional notation (e.g., using fraction pieces to show that three fourths is bigger than one half, but smaller than one whole)

Context

Whole class while reading the story; teacher working with a small group of 4 or 5 children at a table for the fraction activity

Materials

  • Playdough: one fist-sized lump for each child, as well as a demonstration lump for the teacher
  • Playdough cutter (can also use a butter knife), one for each student and the teacher
  • A piece of blank paper for each student and the teacher (will also help control the mess of the playdough)
  • A pencil for each student 
  • Chart paper and markers
  • Book: Charlie Piechart and the Case of the Missing Pizza Slice written by Eric Comstock and Marilyn Sadler

Summary

Children will be introduced to the concept of fractions by first reading a picture book called Charlie Piechart and the Case of the Missing Pizza Slice and then as a group will define “fraction” on chart paper. In small groups, children are then shown the process of splitting the playdough into equal parts (teacher will use fractional names to demonstrate) and place the outcomes on labelled place mats (e.g., labelled “whole”, “halves”, etc.). They are then invited to recreate the fractions by using their playdough. As children gain familiarity with fractions and the task, they can begin to explore more complex fractions, and compare fractions. 

Instructions

  1. Read the book Charlie Piechart and the Case of the Missing Pizza Slice, and have a discussion as a whole group on “What is a fraction?” (making sure to refer to the book and the character “Charlie Piechart”). Write the students’ ideas on chart paper and leave this up in the classroom so it is visible as the children work.
  2. Present children with the playdough in small groups and show the process of splitting the “whole” circle into smaller parts. Discuss with the students as you are demonstrating the activity-have students take a moment to carefully observe the splitting of the playdough and talk about what is happening (making sure to use fractional names).
  3. Place the playdough parts on a labelled mat that explicitly states the fractional names (“halves”; “1/2”). Again, leave this visible as the children work.
  4. Provide each child with their own piece of playdough and get them to create a pizza-shaped flat circle (this is the “whole”). As the students are instructed to do this, the teacher will also do the process with them. Now ask the students to divide it into two equal halves. Get the students to place their results on the white piece of paper and label it with correct fractional name.
  5. Repeat step 4, but instead ask students to divide their pizza-shaped flat circle into quarters, and continue this process with various fractions (gauge how well the students are understanding fractions to determine the complexity of the fraction you want them to show).
  6. Facilitate a discussion in regards to regrouping fraction parts into whole; reversing the process. Get the students to put their pieces back together to create a whole circle again.

Look For and Questions to Extend Student’s Thinking

  • What fraction is bigger, a half or a quarter? 
  • How many quarters will make a whole?
  • How many parts are there when you divide your whole in half?
  • what happens when you take one piece away from the fraction? How many pieces have you taken away and how many pieces do you have left?
  • Do children understand how to divide the whole object into various parts and are they able to name the associated fractional name to their outcome? Are they able to create two halves out of a whole? Do they have difficulty with this task or are they able to compose the fractions with ease?
  • Can children regroup fractional parts back into the whole? Do they understand this concept?
  • Can children compare fractions? Do they understand that one half is the same as two fourths?