This month on Econlib, Donald Cox has a great column on economics for parents:

Ever since I started the mind-bending journey that is parenthood—my wife and I have a daughter in first grade and a son in preschool—my appreciation for economics has roughly quadrupled…

Case study #1: It’s go-home time at my daughter’s preschool. I see a parent struggling to get snow pants on his toddler in an 80-degree room. I think: “Where’s the incentive compatibility in that?” I do it the easy way: I scoop up my daughter in my right arm and her winter clothes in my left and out the door we go. Whereupon, in the 30-degree cold, she dons her winter duds at a speed rivaled only by local firefighters answering a call.

The only problem: Most of Cox’s advice is aimed at parents of young kids, but most of the anguished parents I know have teen-agers! In particular, I know a number of parents who have 18-year-olds who refuse to go to school or get a job. What’s a parent of a teen-age bum to do?

The simple answer, of course, is “Kick the bum out of the house and let him learn about real life!” The problem with this approach, unfortunately, is that it is not credible. When push comes to shove, most parents would rather let their kids shamelessly take advantage of them than throw them out on the street.

“But I’d take him back as soon as he got a job or enrolled in school!” Bad idea. If you’ve got a bum on your hands, he’ll know just how to play you for a fool. To get back on the free room-and-board gravy train, he’s only got to mail in a college application. And you won’t be able to prove that he’s slacking until you see his first semester’s grades! If you insist on a job, he can do the bare minimum, get fired, and wait for you to start threatening him with eviction. Soon you’ll be caught in a dreadful cycle: (1) Your kid slacks; (2) You make escalating threats until you boot him out; (3) He makes a token effort to appease you, but soon resumes slacking; (4) Repeat.

What then? Here’s the least bad solution I’ve come up with:

(1) Tell your slacker he’s got a year to show progress in school or get serious about a job, or he’ll be booted out. Add that if you do kick him out, he can’t return until he’s got results – not good intentions – at school or a job.

(2) Stop nagging him. Save yourself the grief. At most, visibly cross off days on the calendar.

(3) When the year’s up, follow through with your threat. After a year of watching him eat your food and watch MTV, you will be ready to harden your heart and carry out your threat.

Any other ideas? Any evidence, anecdotal or otherwise?