Here's what I came up with:
- 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.
- Lightweight, easily flips over.
Salsa containers (wheels):
- 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.
- 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:
- 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!
- Newton's third law: for every action, there's an equal and opposite reaction
- 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.