Astonishing Science. Spectacular museum.
In this activity you can balance 15 nails on the head of one nail.
Year groups: 3-6 (ages 7-11)
Nail Trick activity sheet
Download student activity sheet [pdf]
This activity works best as an open-ended challenge. Click here for a guide to planning open-ended investigations in your classroom and use the activity sheet only as a last resort, once one child or group has already cracked it, to enable the rest to become experts.
If you want to assemble the equipment quickly, fix the nail upright in a ball of modelling clay or use any smallish flat piece of wood and hammer the nail into the centre. If you want to repeat this activity, cut a piece of wood or MDF approximately 10 cm square and drill a partial hole in the centre that is just wide and deep enough to accept the first nail. This apparatus can then be taken apart and stored flat when not in use.
The larger the nails, the easier and more impressive the activity is, so get the largest ones you can find (make sure you sand down the sharp points).
Look at the crane in the picture. How is it able to pick up very heavy weights without falling over?
CranesCranes use a counterbalance - a heavy weight at one end of the arm that stops the crane toppling over when it picks up a weight at the other end of the arm. This makes cranes very heavy and hard to transport, so some have been designed to use a refillable water tank as the counterbalance to make them lighter and easier to transport.
Construction of the Wellcome Wing at the Science Museum, London, 11 September 1998.
Cantilever bridgeThe railway bridge across the Firth of Forth in Scotland contains almost 54,000 tons of steel. When it was completed in 1890 the 2.2-km-long bridge was the biggest in the world. It is the world’s oldest cantilever railway bridge and remains in use to this day.
The Forth Bridge