What is Glass made of?

<p>&nbsp;How was glass discovered?&nbsp;How is glass molded into so many things?&nbsp;Why is glass sometimes clear and sometimes colorful? For free home activities sign-up at www.WhoSmarted.com</p><p>See Privacy Policy at <a href="https://art19.com/privacy" rel="noopener noreferrer" target="_blank">https://art19.com/privacy</a> and California Privacy Notice at <a href="https://art19.com/privacy#do-not-sell-my-info" rel="noopener noreferrer" target="_blank">https://art19.com/privacy#do-not-sell-my-info</a>.</p>