Grade 5 - Adding and Subtracting Fractions Unit
The Adding and Subtracting Fractions Unit involves using a variety of methods to join or separate parts referring to the same whole. Questions to answer may include:
- Why must we refer to the same “whole” when adding or subtracting fractional parts?
- How can a number line be used to represent adding or subtracting fractions?
- How can benchmark fractions help to determine whether a sum or difference is reasonable?
Math Concepts and Skills:
The student creates and uses strategies for positive rational number computations in order to solve problems.
The student is expected to:
- represent and solve addition and subtraction of fractions with unlike denominators (including mixed numbers) referring to the same whole using objects, pictorial models and a variety of strategies such as:
- using properties of operations
- using the relationship between addition and subtraction
- replacing given fractions with equivalent fractions
- using benchmark fractions to justify reasonableness.
Summative Assessment Task
Students determine if two boys ate the same amount of pizza, or if one boy ate more than the other.
Instructional Tasks/Formative Assessments
Students determine how many whole pizzas five boys need to order, and how much each boy will pay for the pizza slices they eat.
Students determine who ate the most cake, how much more cake they ate, and how much cake is left.
Students determine how long it takes the itsy bitsy spider to climb out of the water spout.
Students use pattern blocks to design a necklace and determine the cost of the necklace with given fractional values for each pattern block shape.
Student determine how many hours Alice needs to work at her job to have enough money to buy a game player.