Gather round! This is an excellent teaching opportunity.
This is an example of a gadget created by a "designer". There seem to be a lot of these around the Internet lately. Note that these designs are just that, designs. They don't work and no one ever claimed they would. It's someone saying "wouldn't that be cool if..."
If you see a futuristic gadget, Google it and see if it's real, or just a concept. Was it made by a "designer" or an "engineer"?
Everyone saying an eraser made out of pencil shavings would be useless is exactly right. This would be useless, but "wouldn't it be cool if pencil sharpeners made erasers?"
This is an example of a gadget created by a "designer". There seem to be a lot of these around the Internet lately. Note that these designs are just that, designs. They don't work and no one ever claimed they would. It's someone saying "wouldn't that be cool if..."
If you see a futuristic gadget, Google it and see if it's real, or just a concept. Was it made by a "designer" or an "engineer"?
In this case, designer it is:
http://www.yankodesign.com/2010/05/24/sharpen-pencil-get-eraser/
Everyone saying an eraser made out of pencil shavings would be useless is exactly right. This would be useless, but "wouldn't it be cool if pencil sharpeners made erasers?"