There are no laws concerning children and front seats. There is a law about children and the use of child safety seats.
No special law exists to children riding in the front seat. Texas requires all children under 8 years of age or under 4'9" to ride in child safety seats. Texas law requires front seat occupants drivers and passengers to be in seat belts.
not allowed
you must spit on their head and shove it out the window
12
They can ride in the front seat if their feet touches the floor when they are sitting straight up.
40 lbs.
I found a really helpful PDF put out by the Utah Safety council. According to it, there is no law regarding children riding in the front seat of the car: http://www.utahsafetycouncil.org/assets/pdf/utboosterlaw.pdf It is recommended that children under age 12 ride in the back seat, or to turn the airbags off if a child under 12 is in the front seat, but there is no law saying you have to.
Anybody can ride in the front seat in New York, but New York government recommends that nobody under 12 sits in the front seat.
Children under 12-years of age must be restrained in the back seat of a car in the State of Texas.
You may not ride in the front seat of a car till you are 13 or older and must be over 85 pounds but this does not apply to cars without a back seat.
Every state has different laws and regulations about when a child can legally sit in the front seat of the car. On average, a child must be at least 8 years old to sit up front in a vehicle.
In the US, under current law, this is probably illegal in every state, though I'm not positive about that. The usual cutoff age for riding in the front seat is 12.