Arduino is an electronics platform board with a processor, inputs, outputs and an easy to use development environment. The most important point about arduino is that its open source hardware. The board design and schematics are available, anyone can build an arduino board on their own.

This board is the best to start experimenting with interfacing various devices. The programming is done in C and its quite easy to code. Every college should buy this and make this available to the students.

The board consists of a ATMega168 processor, 6 PWM pins and 6 analog pins. The output of all these pins can be easily controlled by a C program. The board has various versions option like serial, usb and bluetooth. All these can be added to the basic board with minor modifications.

This video will get you started.

http://s1.video.blip.tv/0980000765166/Make-IntroductionToTheArduino640.m4v

The arduino community is very active and very helpful. They will help you with advanced stuff.