Why do I have to use a number 2 pencil?
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Should we get rid of standardized testing?
Although standardized testing is a particularly hot topic in education right now, this approach to measurement has been in use for two millennia. And while the results of standardized testing can help us understand some things, they can also be misleading if used incorrectly. So what do these tests actually measure? And are they worthwhile? Arlo Kempf investigates.
Which is stronger: Glue or tape?
The oldest glue in the world is over 8,000 years old and comes from a cave near the Dead Sea. Today, we have enough types of tape and glue to build and repair almost anything. But what gives glue and tape their stickiness? And is one stronger than the other? Elizabeth Cox explores the world of adhesives.
Additional references
Ever wondered about the lead in pencils? - The Washington Post
Despite the name, they have never been made of lead.
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