Tom Tom Sawyer Sawyer

Day:Day:

Raft Raft BuildinBuildin

gg

What makes What makes rafts work?rafts work?

• Remember FORCE?• A force is a push or a pull• A river flows because of the force of

gravity on the water (current)• When a raft is placed in the water, it

is “pushed” by the force of the river

What makes What makes rafts work?rafts work?

• Keep FRICTION in mind• Friction is a force that resists

motion between two objects in contact (fluid friction)

• Think about what you can do to minimize friction between your raft and the water

What makes What makes rafts work?rafts work?

• One last thing to think about…WIND is a force, too

• Sails or other structures might help your raft harness this extra force source and move faster!

Fan Fan lineline

Previous WinnerPrevious Winner

Raft Building Raft Building SuppliesSupplies

• 5 Styrofoam cups• 2 pencils or dowels• 2 bamboo skewers• 3 sheets of construction paper• Masking tape• Glue sticks

Raft Building Raft Building SuppliesSupplies

1. Get all supplies at once2. Do not have to use all supplies3. May break or alter supplies4. None will be replaced5. None can be brought from home6. Planning is essential