What is another name for the pound key on the keyboard?

well that's simple. if you use a phone or your teacher sometimes uses it for it means number. #=number key.

that's easy #= number key. to make it short it means number.

# is also called an Octothorpe and is often mistakenly called a hashtag. A hashtag is the tag line AFTER the NumberKey/PoundKey/Octothorpe.