Extending everyone's rappels and tying everyone into the rope before the first person descends is the proper, safest way to do things, unless you wanted all the followers to tie an autoblock as well. It's the quickest, simplest, safest thing to do.
The alternative would be to set up a proper top-belay anchor, lower all your friends from the anchor one at a time, then clean the anchor and rap down on whatever you're leaving behind. Or, you can have you friends rappel by themselves, but keep them on a backup belay with a second rope (also from above, you can also accomplish this using one rope: rappelling on one half, and using the other half as the backup belay). This way they get a chance to give rappelling a try, but you've got an extra line on them incase they slip up.