What effect could one person's invention have on the human race? In the case of the Neolithic Agricultural Revolution, small improvements in farming methods led to increased food production. The human population began to boom, leading us...

Barbed wire may have made cattle farming easier, but it brought to an end the free-roaming days of the plains. No longer could Native American groups continue their nomadic lifestyle, and the days of cowboys herding large groups of...

Those corn husks can be put to good use. Future engineers design and build a new, biodegradable bag for potato chips out of corn husks. They test out their bags by shaking, dropping, and tossing them, as well as placing them in water.

Take a trip through time. A lesson resource provides instruction on the origin of current measurements for time. The text explains the different tools humans used throughout history to measure time as well as provides examples such as...