Setup a publically accessible Linux box at your school. Load the development server with a selection of text editors to experiment, Sun Java JDK and screen (if using Ubuntu, everything is installable by running just one
apt-get(1) command). Give each pair a shared account on the machine. Have them connect to the development server using what ever SSH client they please (Terminal.app + command line ssh on Macs, what ever GUI terminal emulator on Linux clients + command line ssh or Putty for Windows clients). First one to log in starts a
screen(1) session. Second one will attach to the session by running
screen -x. Now they both share the console session in real time. Both can type input and the other one will see the updates immediately. Have them write code using any Unix text editor such as vim or emacs (or pico or jed or what ever for wussies).
Summa summarum.
- It can't get more text based than this.
- Connection will be perfectly usable over a low-bandwidth link (though you should have reasonable latency, say 100ms or less, for jerk-free operation).
- Minimal requirements at student's end
- Having to work on text-based command line may sound a bit kinky at first if the student's are not familiar with it, but hey, you need not to be a long-bearded Unix weirdo in order to set up and use this kind of system. It's really simple when you think about it and let your prejudice go and spend 15 minutes learning the basics first.
- Definitely free as in beer and freedom!