need help building underwater RC robots

I'm a local science teacher and am trying to make my underwater ROVs remote controlled instead of tethered.  This is a big physics project I do with my freshmen students every year.  I am slowly gathering the materials I think I need but have no idea how to do RC stuff, never done it before, but am very proficient in the wired kind. 

Would anyone be willing to volunteer a few hours to show me how to build two motor setups?  I'll buy pizza!

What is the approximate size and weight of the pieces you are trying to control? Also what functions are you looking to achieve? Just forward back motion or more complex movements? Sounds like an interesting project for sure. I'm sure one of us here can help you out with your endeavor. We may even have some electronics we could donate for the kids.


EDIT:

I saw you mention a control via tether. I assume this means power also? What source does the bot use AC or DC?

Angela - You might be in luck.  This coming Saturday is the local robot club meeting here in Grants Pass.  You should be able to find details in the EVENTS section on the main page.  Lots of guys there to answer questions.  Won't even cost you any pizza. 

...Tiger

Hi highlandcrawler
I used to build the ROVs out of PVC pipe, powered by a car battery.  To shrink it and make it non-tethered, I'm thinking of 1/2" irrigation tubing for the frame, maybe make the whole thing about 1 foot diameter, powered by three small motors.  Enclose these motors, receiver, etc in a plastic peanut butter jar with holes cut in it.  The three motors need to go in both directions so the ROV can go forward, back, and up/down and all three need to be independent so the whole thing is easily manuverable.  then attach the jar to the frame.

Tiger
I looked under the events section and saw lots of things.  Can you tell me the specific one that is in Grants Pass?  That might be a good idea for me to go to and get the help I need.

Angela - It's a lot easier if you look on the calendar from the menu at the top of the page.

Thanks for the suggestion on the event Sat night.  I think I'll try to make it, would be very helpful just to talk to some people.