I love those Fords. Reliable, RWD, V8, easy to fix and not too bad on gas either. if your kid likes them it can get them interested in working on them because if you buy a normal Crown Vic or Grand Marquis etc you can get the dual exhaust and other goodies off a police package and if you get a police package there are any number of parts you can get off of other ones to make them nicer even as simple as rims.

It should be kind of obvious but put some guidelines down and get something that your kids like because they'd be more likely to treat it better then a car that they're stuck with that they hate.