Pascal's Triangle; “As far as the laws of mathematics refer to reality, they are not certain, and as far as they are certain, they do not refer to reality.” ―Albert Einstein Read more at http://izquotes.com/author/albert-einstein/3 ;

Building a Squidy (Cartesian Diver) is a great way to review Pascal's Law, Boyles Law, and Archimedes Principle. Glass eyedroppers work well as is, and plastic pipettes and a small nut if the students want to keep them. This is one small part of my Introduction to Gas Laws lesson bundle.