Short description A hole is placed in the side of a full bottle of water but mysteriously no water escapes - until the lid is opened. In this lessons students use ideas about atmospheric pressure and the skill of constructing explanations to figure out how the trick works. Learning objective Communicate ideas: Use force diagrams to show how the mystery works. Pressure: Explain how the mystery works in terms of the effects of unequal force. Blueprint curriculum link Unit: Heating & cooling Concept: Pressure: Particle motion causes gases to produce pressure on the containers, which depends on their temperature Skills: Write: Use diagrams to communicate Learning stage: Acquire Activity contents Teachers guide PowerPoint file The activity is delivered as a zip file. After you checkout, you will be sent an email with the link to download it.