Experimental speakers

[joetech]

I teach Technology in a High School. One of my courses is a Tech survey course that covers everything from Digital Photography to mechanism to CAD to basic electricity to... you get the idea. I am considering making a unit of Audio.
I would like to show the different between cheap and good speakers(who knows maybe some of that crap in hear coming out of their cars isn't so bad, just sounds that way). I would also demonstrate the difference between ported and sealed cabinets, size of the port and different crossover points.
It would be a tremendous task to do all of this from scratch.
I was hoping someone may have an idea of some existing gear or designs. I would rather not re-invent the wheel.
Also keep in mind that I have almost no money to spend. I will be looking for donations.

[augerpro]

Over at avsforum.com they have a very active Do-it-yourself subforum under the loudspeaker forum. I'm sure you would find a wealth of info on theory, design, and execution.

[jaxvon]

I would be willing to bet that some manufacturers out there are willing to give out donations. In my experience, they love giving deals and free stuff to educational facilities. You just have to make a good case.