DESCRIPTION Here is a complete unit to introduce and teach addition and subtraction equations and word problems to your elementary class. Students will be introduced to solving for a missing number in equations by coloring groups of items two different colors. For example, in Lesson 1 kids are given a nest with 6 blue or red eggs. Students are told there is 1 blue egg and must figure out the number of red eggs in the nest. After they color 1 egg blue, it is easy to color and count that there are