I am genuinely amazed that someone employed in teaching science is as bad at science as my geology teacher. Interesting science-y tidbits I have caught her mangling in class this week:
Silicon is a metal, which is why we use it for electronics.
This isn't true, silicon is not a metal. It is one of the most common elements on earth, and is found in a multitude of minerals and mineraloids, including sand and glass. Silicate elements are used in many applications, from computing to soap to non-stick cookware.
Electrons don't have any mass because they move at the speed of light.
This also isn't true. Electrons are subatomic particles with a mass of 1/1836 of a proton; they are very light, obviously, but they do have mass and are matter, not energy. Additionally, the speed at which electrons travel can approach the speed of light in a vacuum but never reach it. Electrons are considered to be fundamental particles with no substructure, and have an electric charge that is negative and equally strong as the positive charge in protons, which is key for electromagnetism. Many other exciting facts about electrons can be found at wikipedia.org!
It's amazing how useful the Internet is. What did people with shitty teachers do before it was possible to Google things that sound wrong?