Driving Statistics

• Teens are not only the worst drivers, but they tend to cause a high percent of costly accidents. Car accidents, for example, are the number one killer among people 15 to 20 years old. Teens were also responsible for 12 percent of all auto accident fatalities in 2008, according to Rocky Mountain Insurance Information Institute. 15 to17 year old drivers cost a total of $34 billion in medical, property and other related costs to insurers in 2006.
  
  

Male Drivers

• Boys aged between 15 and 18 are generally the most expensive to insure. According to the Insurance Information, teen males caused twice as many car accident fatalities as teen girls. However, this does not translate into much more than a few dollars to per month on a premium.
  
  

Other Factors

• Car insurance companies base teen insurance rates on more than just national driving statistics. There may be many different factors that play into the premium rate. What kind of car the teen drives, the accident rate of the city in which the family resides, the deductible and if they are on the parent's policy also play a large role, according to MSN Autos.
  
  

Tips

• Adding a teen to an existing policy comes with a discount, according to Edmunds. Ensuring the teen receives high marks (a 3.0 GPA or higher) comes with about a 10 percent reduction in premiums. The type of car is important too. Families should avoid giving teens sports cars--they are usually less safe than a modest four-door sedan. Also, if a teen gets a traffic violation, it's important to ensure he takes a driving safety course--if allowed--because this usually removes the citation from his record, and means the insurance premium will not increase too sharply.
  
  

New or Old Vehicle

• Although it costs less to insure an older car for teen drivers, parents should also consider the added risks, according to Insurance.com. New cars have the latest safety features, and an older car may not have anti-lock brakes, which requires a different emergency breaking procedure. Also, old, small cars typically do not qualify for a safety discount and put the teen at an added risk for a fatal accident.