Apparatus, systems and methods for language instruction

Apparent altitude changes in camera model visual system

Appliance for simulating the chewing action of a mammal

Application of multi-media technology to computer...

Application of multi-media technology to psychological and...

Arc welding simulator trainer

Arithmetical teaching aid

Arrangements of maps

Art instructing apparatus

Article de papeterie

Articles with spinning globe

Artificial horizon device

Artificial miniature landscape model with three...

Assembly for teaching mathematical concepts

Assembly for the display and storage of science...

Assembly to demonstrate and teach the game of bridge

Assessment system and method

Assistive communication device

Audience response system and method

Audio dictionary