Museum of Science, Boston

Books for Kids

  • Bubble-ology
    , by
    Jacqueline Barber
  • How Do You Make a Bubble
    , by
    William Hooks
  • Pop! A Book About Bubbles
    , by
    Kimberly Brubaker Bradley & Margaret Miller

Contact Us

Contact the Discovery Center and Living Lab staff at livinglab@mos.org

August 2010: Bubble-ology

Bubble-ology

Children love bubbles! Whether blowing, chasing, or popping bubbles, children are fascinated by the floating, iridescent spheres that seem to defy gravity while elegantly soaring around.

The Bubble-ology activity allows children to explore the science concepts of surface tension, air pressure, light and prisms, in a fun and interactive way. While many children have experience playing with bubbles, this activity will help them think about the science behind bubbles, and challenge them to explore the properties of bubbles by participating in a variety of engaging experiments.

The Discovery Center’s Bubble-ology activity encourages children to make observations and set a goal. Using a variety of simple tools and materials, such as straws, string, cups, and pennies, children can design their own experiments to learn about bubbles.

Whether trying to blow a bubble bigger than their head, attempting to drop a penny in their bubble without popping it, or aspiring to make a “square bubble,” children are sure to learn through play as they become “bubble scientists.”

Bubble-ology at Home

You can continue you bubble explorations at home by

Creating Your Own Bubble Solution and Bubble Makers

Bubbles Solution Recipe:

  • 2 c. water
  • ¼ c. high-glycerin content dish soap
  • Optional: 1 T. glycerin (available at health food stores, or science supply companies online)
  • NOTE: This “recipe” is just a starting point. The ratios do not have to be exact to make great bubbles!

      Bubble Maker Ideas:

      1. Poke a hole on the side of a plastic cup, towards the bottom. Cut a straw in half, and push one end of the straw into the hole in the cup. Now you can dip the open end of the cup in bubble solution, blow through your straw, and watch as bubbles come out the open end of the cup!

      2. Try making a square bubble frame! Thread two straws on to a string and tie the string closed. Stretch the straws apart to create a square.

      3. Try making a triangular bubble frame! Thread 3 straws on to a string and tie the string tight, so that there is no excess string, to create a triangle.

      4. Try tying the straws together to make a 3-dimensional bubble maker, such as a pyramid or cube.

        Questions to think about while experimenting:

        • What is a bubble made of?
        • What color is a bubble?
        • What happens when you use fast air to make a bubble?
        • What happens when you blow slowly to make a bubble?
        • What shape is a bubble?
        • Are bubbles always round? Why?
        • Can you make a bubble as big as your head (or bigger)?
        • How can you put your finger through a bubble without popping it?
        • Can you hold a bubble in your hand?

          Thinking about the Science of Bubbles

          Bubbles are the result of surface tension and air pressure.

          Surface tension is like a stretchy film of liquid caused by water molecules at the surface, which cohere to the water molecules just below more strongly because there are no water molecules above them to cohere to. Bubble films are sandwiches of soap and water molecules. When you blow through a soap film, the stretchy skin of the water’s surface is pushed outward and forms a bubble as you fill it with air.

          A bubble is always circular because its surface is pulled into the shape that has the smallest surface area, which is a sphere. Air pressure inside and outside of the bubble is equal, so all free-floating bubbles will eventually become rounded, because the air pushes on the soap film equally all over the bubble and the surface tension that hold the molecules of the bubbles together pulls equally in all directions.

          *In this drawing, the water molecules are red and white, and the soap molecules have long blue tails*

          The changing colors we see on soap bubbles are caused by the interference of light waves. When white light hits the outer and inner surfaces of a bubble, the bubble’s surface reflects the white light as many different wavelengths (colors) of light. The frequency of a light wave that is reflected determines what color you see.