One of the more classic ways to launch a balloon is using a sling. A sling has a pouch secured between two retention cords. Some sling balloon launchers use elastic bands as the cords. The pouch is loaded with a water balloon and pulled back (action), then let go to make the balloon fly (reaction). Will you use a sling in your launcher design? If so, what will you make your pouch out of, and what kind of retention cords will you use?

If you are thinking of building a catapult launcher, you will use a simple machine called a lever. A lever is a rigid beam that rests on a pivot point. One type of lever called a trebuchet, is a type of catapult that uses a long arm, the principles of leverage, and a counterweight to throw the projectile (in this case, a water balloon). The projectile can be put into a holding area like a sling attached to one end of the beam, and as the beam rotates, the projectile is flung out and away from the machine. How would you use a lever in your launcher design? Will it be a trebuchet or something else?

Have access to tools? Computer software? 3D printer? Invent a more complex launcher with high-tech tools. With technology, there are no limits, but as always - use parental supervision with tools!

To get the water balloon in the air, you will need power! What will your launcher be powered by? Human strength, electricity, air pressure, or something else. Think about how your design will tap into and maximize its power source.

What will your launcher be made from? How will these materials work together to launch a water balloon? For example, where will you load your water balloon and where will it go from there? Take some time to sketch out a design and include the materials you plan to use.

Brainstorm any idea that relates to your launcher design. The possibilities are endless!