Previously, students used various strategies and representations to reason about the relative size of fractions. In this lesson, they focus on writing equivalent fractions as a way to compare fractions. Here the denominator of one fraction is a factor or a multiple of the denominator of the other fraction, making it likely for students to see one fraction in terms of the fractional part of the other. In a future lesson, students will compare fractions in which the denominators have no common factors.
- Compare two fractions by rewriting one of them into an equivalent fraction with the same denominator as the other.
- Let’s compare fractions by writing an equivalent fraction.
|Activity 1||20 min|
|Activity 2||15 min|
|Lesson Synthesis||10 min|
Teacher Reflection Questions
How readily did students grasp the idea of writing equivalent fractions with a common denominator as a way to compare fractions? What evidence did you see of students connecting it to the reasoning they did about equivalent fractions on number lines? How could the connections be made more explicit?
- Mystery Number (1–4), Stage 4: Fractions with Denominators 5, 8, 10, 12, 100 (Addressing)
- Compare (1–5), Stage 3: Multiply within 100 (Supporting)