Science 8 – I love this lab. Students predict what they’ll get when they mix 50 mL of water with another 50 mL of water, and then they find out that it’s almost 100 mL. They do the same with 50 mL of water with 50 ml of ethanol. To their surprise, it only adds up to around 97 mL. Finally they mix 50 mL of sand into 50 mL of marbles. They now have a model for how matter is made up of particles and how there are spaces between the particles. Students also learn about miniscus, graduated cylinders and brainstorming errors (why did 50 mL of water + 50 mL of water = 99 mL?).