What should the authorities do?
The obvious thing to do is to get a warrant and seize all computers and printers in the home, and arrest the parents and charge them with felony counterfeiting. 
They obviously have either a very high Dex or the feat Improved Initiative.
Wow. This sounds almost exactly like what happened a few months ago in my old high school, except that the kids were in 10th grade, they made $100 bills, and now they’re being charged with forgery.
They might have used a Scimitar of Speed, or cast Haste.