Noise canceling headphones also are not very good with rapidly fluctuating sounds like kid noises. Echo the risk to driving safety of wearing any headphones.

As far as I know, there are no laws forbiding such a use outright. However, there are laws on the books that say you should be driving in a safe and prudent manner. The problem with noise cancelling headphones is it will cancel out the noise of your kids as well as the noise of everything around you. This could be very dangerous in a situation where emergency vehicles are coming up behind you needing to pass, and it situations where other drives are trying to alert you to potentially dangerous situations.

For these reasons, and for the safety of your family, I would not recommend them while driving. If you are a passenger -- go for it! For the driver, I recommend a good classical music station :-)