Unit 2, Lesson 3
El mismo denominador o numerador
Grado 4
Preparation
Lesson Narrative
In this lesson, students reason about the relative size of fractions based on the meaning of their numerators and denominators, and use fraction strips to support their reasoning.
Students first compare pairs of fractions with the same denominator but different numerators. They recall that fractions with the same denominator are composed of the same unit fractions or have parts that are the same size. So, the numerators (number of parts) can tell us how the fractions compare: the greater the numerator, the greater the fraction.
Next, students compare fractions with the same numerator but different denominators. They recognize that these fractions have the same number of parts, but the size of the parts are different. A greater denominator means more parts in 1 whole, which means the size of each part is smaller. So, the greater the denominator, the lesser the fraction.
- Engagement
None
- Describe (orally) characteristics of the numerators or denominators when comparing fractions with the same numerator or same denominator.
- Explain (orally) strategies for comparing fractions with the same numerator or same denominator, including using physical or visual representations.
- Comparemos fracciones que tengan el mismo denominador o el mismo numerador.
Required Preparation
None
Teacher Reflection Questions
Most students may find it more intuitive to compare fractions with a common denominator than those with a common numerator. Did you see students who grasp both comparisons equally well? How did they conceptualize the latter?