Make a rolling toy:
Balloon-powered racer
This balloon-powered racer is easy
to make and fun to play with.
What you need:
• 4 plastic bottle lids
• pair of drawing compasses
• 2 wooden skewers
• scissors
• 15 x 10 centimetre
rectangle of thick card
• 2 straight straws
• sticky tape
• bendy straw
• balloon
• elastic band.
Ask a
carer
teach or
er for
help.
What to do:
1 Ask an adult to make a
hole in the middle of each
bottle lid using the point of
the compasses. The hole
should be just big enough
to fit a skewer through.
3 Tape the straight straws
to the card.
2 Cut the points off the
skewers using the scissors.
4 Put a skewer through
each straw.
The force of the air
coming out of the balloon
pushes the racers along.
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5 Put the lids on the ends
of the skewers.
7 Cut the straight end off
the bendy straw.
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6 Turn the racer the right
way up so it is resting on
its wheels.
9 Tape the bendy straw to
the racer.
10 Blow through the bendy
straw to blow up the
balloon. Pinch the bendy
straw to keep the air in.
8 Fix the balloon to the
bendy straw using
the elastic band.
11 Let go of the bendy straw
and watch the racer go!
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How forces make rolling
toys work
This table shows some of the pushing and pulling
forces that act on rolling toys.
Forces make
toys …
Pushing or
pulling force?
Example of the force acting on a toy
start moving
pushing
force
A rollerblade starts
moving when a pushing
force acts on it.
both
A bicycle changes
direction when a
turning force acts
on its front wheel.
change
direction
speed up
slow down
stop moving
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pulling force
A billycart speeds
up when a pulling
force acts on it.
pushing
force
A skateboard slows
down when the pushing
force of friction acts
on its wheels.
pushing
force
Glossary
axles
r ods that pass through the middle of wheels,
and work by holding the wheels in place and
allowing them to turn
friction
a force that slows down moving objects
by acting in the opposite direction to
the direction the object is moving in
gravity
the force that pulls objects towards Earth,
and acts on everything, all the time
impact force
a force that acts on a moving object when
it hits something
rolling
oving along the ground by turning one part
m
(for example, the wheels) over and over
surfaces
the outside or top layers of things
turning force
a force that causes something to turn, made up
of a pushing and a pulling force working together
wheelsround discs with an axle through the middle,
which work by turning around the axle
A toy car stops when
a large enough impact
force acts on it.
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