Combine 1 cup baking soda and 1 tsp gelatin powder in a bowl.
In a seperate bowl, mix food coloring with the ¼ cup water.
Add the colored water to the baking soda and gelatin powder mix and stir.
Spoon the mixture into an ice cube tray and freeze.
Repeat for as many colors as you would like.
Place frozen fizzy ice cubes in a bin or dish.
Use the droppers to add vinegar to the ice blocks for fizzy fun!