Pour the entire bottle of Elmer's color changing glue into a medium sized mixing bowl.

Add 1/2 cup water to the glue and mix well.

Add 1 teaspoon baking soda to the bowl and mix. 

Add 1 tablespoon contact lens solution to the bowl and mix with the fork. 

Once the slime begins to stick to itself, use your hands to knead and mix the slime until it reaches the consistency you'd like. If after working it with your hands it's still too sticky, add a small amount (about 1/2 tablespoon at a time) of contact solution and mix again. We used a total of 3 tablespoons plus 1 teaspoon contact solution.

Bring your simple slime outside and watch it changes colors before your eyes!