Think Outside the Crowbar
The trouble with drywall over beadboard is that you can't just bang on the drywall with a sledgehammer. It does no good and might damage your beadboard. I've also tried cutting the drywall with a box cutter, but that pesky bottom layer of paper on the drywall is hard to cut without also slicing into the beadboard.
Using a hammer (alternating the claw end and the um ... other end), then a crowbar, this is how far I got on our bathroom drywall-over-beadboard:
I expected the crowbar to be the magic solution. Ah-ha! I'm using the proper tools for once! It HAS to work!
Alas, that was not the case. The crowbar actually worked less efficiently than the already-inefficient hammer method. *SIGH*
I hope somebody out there has an idea. Somebody? Anybody? If I have to remove an entire bathroom full of this stuff this way (that patch above is maybe 1 foot by 2 feet), including ceilings, it will take me approximately 275.867 years.
Please help, O Creative Ones!