Kid President - How To Change The World with Kindness. Teaching kindness to children is part of the fourth National Health Education Standards: Students will demonstrate the ability to use interpersonal communications skills to enhance health and avoid or reduce health risks. Learning to be kind helps build a positive learning environment.
The stone-throwers took two forms-either like the arrow-firing apparatus or large one-armed catapults, known in the 4th century CE as the onager or 'Wild Ass' because of its terrific recoil but, in fact, first appearing in the 2nd century CE.
Almost 10,000 years later, as settled communities were established, tiles were manufactured in Mesopotamia and India. The first use of functional pottery vessels for storing water and food is thought to be around 9000 or 10,000 BC. Clay bricks were also made around the same time. Glass was believed to be discovered in Egypt around 8000 BC, when overheating of kilns produced a colored glaze on the pottery. Experts estimate that it was not until 1500 BC that glass was produced independently of ceramics and fashioned into separate items. Fast forward to the Middle Ages, when the metal industry was in its infancy.