Homemade temporary hair color for children can easily be made using food coloring, Kool-Aid or chalk. These DIY solutions are preferable to permanent hair dyes because children's hair is typically thinner and more fragile than adult hair, and it can easily be damaged by even the most gentle hair-color formulas. Also, children's skin and scalp are more tender, sensitive and prone to allergic reactions.
To dye hair with sidewalk chalk, soak the chalk in a bowl of water for 5 to 10 minutes, and then grind it to create a paste. Apply the paste to damp hair. Allow the hair to dry, tip the child's head upside down to shake out any excess chalk, and spray the hair with hair spray. To dye hair with artist chalk, also known as chalk pastels, simply apply the color onto wet hair, and then heat seal it with a flat iron. Although it is not necessary to use the flat iron, that ensures the color will last until it is washed out.
To color hair with Kool-Aid, combine the drink powder with mayonnaise or hair conditioner and apply the mixture to the child's hair. Cover the hair with plastic wrap for 60 minutes and rinse. For a quicker method, add 5 or 6 drops of food coloring to a small amount of hair mousse or gel, and massage it into the hair for instant color.