Task# Buttons odd and even

Illustrative MathematicsVaries

The purpose of this task is for students to determine whether a set of objects (up to 20) has an odd or even number of elements. Students will also write an equation to express an even number as a sum of two equal addends and an odd number as a sum of two equal addends and 1. The goal of writing out an equation for each number is that students experience odd numbers as doubles plus one. To assist in this objective teachers will support students in writing the equations for odd numbers as n+n+1 instead of n+(n+1).