John McCain has frequently criticized Barack Obama for a $3 million earmark for an "overhead projector" for a planetarium in Chicago. Paul Knappenberger, president of Chicago's Adler Planetarium, ...

I don't like using PowerPoint in the classroom, so I usually use a blackboard or an overhead projector. What I'd like to do is write on a projector-connected iPad, have the screen content projected on ...

Placing a Plexiglas block on top of a mark on an overhead projector decreases the apparent depth of the mark. Turn on the projector and put the transparency on it. Focus the projector. Put the block ...

I worked for a company that made overhead projectors. The company had just come out with a new line. The new projectors were significantly smaller than the previous models. I was contacted by a member ...

A lot has been said and written about the earmark Barack Obama sought for a new $3 million overhead projector at the Adler Planetarium since John McCain raised it in Tuesday night’s debate. And a lot ...