4th Grade Lesson: Comparing Fractions: Slicing Sandwiches

Students use Scratch to compare fractional parts of sandwiches with the same denominator to determine which is larger. They use variables to represent fractions in comparing multiple conditions.

Resources for Comparing Fractions: Slicing Sandwiches

computer-based

Activity Summary

Students use Scratch to compare fractional parts of sandwiches to determine if sandwich A is greater or less than sandwich B. They will program the computer to cut the sandwich in equal parts (based on the denominator) and then display a certain number of these sandwich parts (based on the numerator). They will program inequality rules and the computer will compare the fractions and identify the correct inequality symbol.

Math Connections

Students compare fractions with the same denominators using a number line and a visual (sandwich). They discuss rules, such as the same denominators mean that both wholes will be divided into the same number of parts, each part is the same size, the smaller the denominator the size of the parts is larger, and that the numerator and denominator together will determine the inequality.

CS Connections

The students use variables to represent fractions in comparing multiple conditions which will result in different results (true or false). Students work with conditionals to compare fractions and validate the result. Students will see how the use of variables in conditionals can give different outcomes.

Topics

• Repetition
• Conditionals
• Variables
• Comparing fractions: (Same Denominator)