What you need

• Plastic box
• Sand
• Water
• Smooth brick or other heavy object
• Rubber mallet

Instructions

1. Fill half a plastic box with sand
2. Add water until it fills up to just below the level of the sand
3. Place a heavy object upright in the sand
4. Tap the side of the box with the mallet and you'll notice the object will begin to fall over

Results and Explanation

Tapping the side of the box makes the sand particles move over each other, making the heavy object fall over.

These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.