Make It Move

50-60 minutes

• Set out cardboard strips, brass fasteners, string, and tape per team, plus one light object to lift such as a crumpled paper ball.
• Mark a 'target spot' on each table so students can practice placing the object, not just lifting it.
• Demonstrate a pivot first: pin two craft sticks with a fastener and show how they turn around it.

• Pre-punch fastener holes in a few cardboard strips for students who struggle with the poke-through step.
• Cut string into roughly 40 cm lengths for the crane builders.

• Brass fasteners and any hole-poking tool are sharp - poke holes down onto the cardboard on the table, never toward a hand.
• Scissors are passed handle-first and stay on the table.

• Point to the pivot and explain that a lever turns around it.
• Explain that string can pull but not push.
• Explain that a small movement at one end can make a bigger or stronger movement at the other.

• Fasteners pinched too tight so the arm will not move, or too loose so it flops.
• A grip that pushes the object away instead of closing on it.
• A crane string with no way to hold tension, so the load drops.

• "Where is the pivot, and what happens if you move it?"
• "Which part acted like a lever?"
• "What made the grip drop the object?"
• "How could you get more lifting power without adding more cardboard?"

Start everyone on a two-strip 'clothespin' grabber and skip the crane, so there is only one pivot to manage.

Require the machine to reach 30 cm, or to pick up a rounded object like a ball.

• Recover reusable brass fasteners and string into a small container.
• Recycle cardboard scraps and keep larger offcuts for next time.