To make bubble art you will need the following supplies: 1/2 cup of bubble solution, at least 1 tbsp. powdered or liquid tempera paint, a small bowl, a spoon, colored paper of a light hue, and one drinking straw per child. Put the bubble solution and paint into the bowl, then mix with the spoon until well-blended. Dab some of the mixture onto a piece of paper to check color and add tempera paint until the desired color is reached.
To create the art, stick a straw in the mixture that you made and have a child gently blow through the straw, stopping when the bubbles are higher than the edge of the bowl. Lightly place the paper on top of the bubbles until they pop. Repeat blowing and pressing until the paper is covered enough to suit the child. For children who cannot yet blow, you can help them trap some of the paint solution in their straw by placing a finger on top of the straw while it is in the solution, then dabbing it on the paper. This will create small bubbles that pop without the blowing.
Motor skills are still developing in children this age, so be patient and ready to assist children with blowing. Hold the straw for them and give them a familiar reference point for blowing by telling them to blow "like I do when your food is hot" or "when you are blowing bubbles outside." Pay attention to why a child might not be making bubbles, such as his grasping the straw with his teeth or sucking instead of blowing.
Preschoolers will often suck instead of blow, so make sure you use nontoxic paint and have enough supervision to do this activity. Use light-colored straws so you can see if a child is sucking the mixture up, and be ready to squeeze the straw together to stop sucking if it happens. Have water and towels nearby to rinse out a mouth or wipe up a spill. If your preschool has toddlers, this activity is not recommended for them, as their motor skills are generally not developed enough to do it safely.