Opposites - Opposites, free printable game (good pictures on this one)
Opposites - The opposite game (printable)
Opposites - Sesame Street - Ernie and Bert sing "Loud and Soft"- would work great for K-1. Also has "long" and "short" and they sing high and low and on different vowels.
Hot or cold - idea to build on for an "opposites" lapbook
Alphabet Safari game - I also did this with colors and numbers! The kids loved it!