The green dice represents positive.
Negative Numbers - Definition, Rules, Examples
Negative number - Wikipedia
Negative Numbers for Young Students – Denise Gaskins' Let's Play Math
Two's complement and negative numbers for integers, by Jhoan Stiven Zamora Caicedo
Adding and Subtracting - Negative Numbers
Positive and Negative Integers Poster
Teach middle school math lessons about positive and negative numbers with this number line with positive and negative numbers.
Positive & Negative Number Mat
Understanding negative numbers
Number Lines: Negative Number Line and Positive Number Line