Balloon Racers

I've been meaning to play with quick and easy materials to find a fun balloon racer to make at home.

Here's what I came up with:

Strawberry containers:

Benefits:

• Many holes = less work for me!
• Basket for the balloon to sit in/attach to easily (I attached it with a rubber band using a girth hitch knot).
• The basket can also carry weights if you chose some of the variation activities.

Cons:

• Lightweight, easily flips over.

Salsa containers (wheels):

Benefits:

• Due to my lack of motivation for cooking and the easiness of a nearby take-out Mexican fast food chain, we have PLENTY of these around the house.
• They are round-ish and bigger than bottle caps.

Cons:

• Hard to poke holes into (cheap plastic).  We tried to drill, ended up with a gentle poke of an awl.

*We used wooden skewers as axles and attached the salsa cups via press fit (you could glue them into place too).

Balloon and straw:

• I used a standard size birthday balloon.
• I attached the balloon to a cheap, standard bendy straw with a rubber band.
• Be careful not to squish the straw with the rubber band being too tight.

Here's how my balloon racer runs:

Variations:

• Try different sized balloons.
• Try attaching it to different size straws (vary diameter and length).
• Add weights (easy with a strawberry basket).
• Try to see if your racer runs on different surfaces (tile, carpet, sidewalk, asphalt).
• Use different materials.  You'd be surprised at what you can make from your recyclables collection.
• Steer your vehicle by placing the straw at different locations/angles and see what happens.

Here's what happens with a bigger straw and our basket:

Why?  The straw wasn't connected straight (hence the crazy sideways motion) and the forces from the straw were so great that the light basket just flipped over!

Lessons learned:

• Newton's third law: for every action, there's an equal and opposite reaction

J's Quote:

• I used making a cool science balloon race car as a bribe for him eating his dinner.  He held me responsible.
• (Passing me the strawberry basket that's been on our counter for a week) "Mommy, let's do science!"
• We got so excited about science that we forgot about dessert.