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Week 09 · Balloon Car

Wednesday

Build car version 1
// A car pushed by balloon air
⏱ about 20 min

Wednesday: Build Car Version 1

Rocket tapes two straws under a cardboard rectangle.

Sticks slide through the straws. Bottle cap wheels go on the ends.

"Done in five minutes!" Rocket says.

Raven asks a grown-up to fill the balloon.

Nova hovers by the start line. "Ready? Let go!"

You need

  • A cardboard rectangle about as long as a ruler
  • 3 straws
  • 2 wooden sticks for axles
  • 4 plastic bottle caps for wheels
  • A balloon
  • Tape and a ruler
Safety first
A grown-up cuts the cardboard and snips sharp stick tips.
A grown-up pokes the holes in the bottle caps.
A grown-up blows up the balloon.
Children under 8 can choke on flat or broken balloons.

Build it

  1. Tape two straws across the bottom of the cardboard.
  2. Slide a stick through each straw.
  3. Push a bottle cap onto each stick end.
  4. Tape the balloon onto the end of the third straw.
  5. Tape that straw on top, pointing off the back.

Test it

  1. A grown-up blows through the straw to fill the balloon.
  2. Pinch the straw and set the car at the start line.
  3. Let go. Measure how far it rolls.
VersionHow far (inches)Past 3 feet?
Version 1
WHICH WAY?
  • Read the question.
  • Tap your answer.
Which way should the balloon straw point?
SAFE BALLOONS
  • Read the question.
  • Tap your answer.
Who blows up the balloon?

Check the wheels

Before you test, spin each wheel with a finger.

Does it turn easily?

Does it rub on the cardboard?

Fix any wheel that sticks.

BUILD CHECK
  • Read the question.
  • Tap your answer.
What are the sticks for?
Who pokes holes in the bottle caps?
How do you measure how far it rolls?
SafetyTrue or false?
A grown-up snips sharp stick tips.?
Little ones may play with broken balloons.?
Throw away broken balloon pieces right away.?
Children cut the cardboard alone.?
WHY THIS EXERCISEGrown-ups handle the sharp and risky parts.
BUILD THE CAR
  • Tap a card.
  • Then tap its spot.
1First
2Next
3Then
4Last
Try it
Build your car with a grown-up.
Spin each wheel with a finger.
Then test it and measure.

Version 1 is on the road!

Tomorrow, we see how far it went.

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