tool for greatly magnifying tiny things - for Stimulating Learning Projects?
see Robert Hooke's MicroGraphia
You can see blood cells at 200x
A Digital Microscope has the advantage of letting you save images easily. (Beware some may have platform-specific software.)
The EyeClops Bionic Eye magnifies 200-400x and connects directly to your TV. And saves images to a USB key to transfer to your computer.
QX5 goes to 200x but has a stand, etc.
lots of choices
add a $1 lens to your OLPC?