The American Academy of Pediatrics updated their car safety recommendations in the April issue of Pediatrics advising parents to keep their toddlers in rear-facing car seats until 2 (or until they reach the maximum height and weight for their seat  for big kids). They also recommend that most children should be in a belt-positioning booster seat until they’re 4’9” and are between 8 and 12 years of age.  They also say that kids should ride in the back seat until they’re 13.  The Injury Prevention Program has trained car seat technicians who can answer your questions, or you can find help here: http://seatcheck.org/