What is rubber? History of rubber
A big rubber tree in Mexico Olmec people, living in southern Mexico, invented rubber about 1600 BC. It was just as they were beginning to build their empire. Rubber starts out as [...]
A big rubber tree in Mexico Olmec people, living in southern Mexico, invented rubber about 1600 BC. It was just as they were beginning to build their empire. Rubber starts out as [...]
This truck has a lot of mass. Mass is a measure of the number of atoms in an object combined with the density of those atoms. Usually people measure mass in kilograms. You can tell [...]
Modern-day re-enactors having a tournament Tournaments were a common form of entertainment in the Middle Ages. A group of knights came together at the castle of some powerful duke or [...]
Chinese science: a double-action piston box bellows (China) What are some Chinese inventions? Chinese scientists started inventing a lot of new things around 500 BC, during the Warring States period. [...]
Kongming's Light, made by kids at Laurelhurst School, Portland Oregon Kites came first People in China started to fly kites made of silk and bamboo by about 800 BC. Maybe flying [...]
A diagram of a hydrogen atom Hydrogen is the simplest kind of atom Hydrogen is the simplest kind of atom, and in the very earliest days after the Big Bang [...]
Diagram of a helium atom Helium is a very simple atom. Helium is a simple atom. The nucleus of a helium atom has two protons and two neutrons. Around the nucleus, [...]
You can see that helium is lighter than air by getting a helium balloon. When you let go of it, it goes up, because the helium is lighter than the nitrogen and [...]
Frozen carbon dioxide (dry ice) - for your carbon dioxide project How can you see carbon dioxide? Normally you can't see carbon dioxide because it is an invisible gas. But [...]