Using XLR Mics with cheap consumer camcorders?

I’m in a broadcasting class at school and we are in a bit of a pinch. We have several little “cheap” consumer camcorders (typical little $200-$300 handheld ones, most of them from JVC but one from Canon and one from Sony) and we keep having problems with our audio. We have lav microphones that we use in a studio (with an actual sound board and actual video mixer) but I’m not sure how we could use those with the camcorders for on-location work. Is there some kind of a “portable sound/video recorder” that we could plug the camera and the microphones up to? I know we could get an audio recorder but I am trying to save them the trouble of manual A/V sync…they only have Sony Vegas Movie Studio and don’t have the computing power to run a “real” creative suite.

Any ideas?

XLR to 3.5mm adapter cables exist that I've personally used and which work quite well. Of course the mics mustn't require any sort of phantom power and there's no way to control the levels on the fly.

That's the problem, I would use one of those with a little 4 channel sound board, but our cameras have no mic input. The only one that does is the Canon, and having 1 camera out of like 7 that supports a feature isn't really a good option...

I was kind of hoping for a relatively affordable "portable video recorder" where we could plug in HDMI and a couple XLR mics and it would record them all in real time to an SD card. If it does phantom power that's great but if not I think we can figure something out for that...ideas?