There are larger than life SpongeBob SquarePants balloons sitting triumphantly atop Burger Kings across America. There's an onslaught of products and advertisements at every turn promoting movies like The Incredibles, all aimed at my three kiddos.

Here's the problem: Those films are rated PG, not G—and my kids include two kindergarteners and a preschooler.

As a parent who'd like to provide pleasure to my children, I want to let them see a funny flick that seems (at least from the ads) to be family friendly and for them to get that fun movie theater experience. But I'm stopped in my tracks by the PG rating and am uncertain of the type of content in the movies. The reviews in the newspaper don't shed much light on how the films would be perceived by my small kids.

So what's a thoughtful parent—someone who doesn't want her children exposed to violence, bad language, or scary scenes—to do? And, while I'm at it, what am I supposed to do to protect my kids from the avalanche of marketing targeted squarely at their hearts and my wallet?

The answer, at least according to one expert on children and the media, is for parents to do their homework on movies and TV shows, examining what exactly is shown in those productions before taking kids into a theater or putting a DVD on and leaving the room to go make dinner. On too many occasions, parents simply allow their kids to view films or shows ostensibly aimed at children, but don't realize what the productions contain and what sort of negative impact (like nightmares and violent imitative behavior) they may yield for the children, says Professor Joanne Cantor, an expert on the effects of mass media on children at the University of Wisconsin-Madison.

But before reading parent-oriented movie reviews—like trying to find out exactly what's in that SpongeBob movie aside from his bizarre laughter—Cantor says parents should understand how media images affect different age groups.

Children Ages 2-7

Protecting children from certain content that may frighten them or goad them into bad behavior requires different approaches based on age, Cantor says. Very young children (two to seven years old) are literal and believe what they see, regardless of what their parents say. For example, you can tell a three-year-old that what happens in a movie like Beauty and the Beast is just pretend. The preschooler may nod, but will likely still believe the violent scenes and the frightening transformation of the Beast into a prince are real. The visuals nullify the explanation. "When they're very young, you have to intervene," Cantor says.

In her book Mommy, I'm Scared: How TV and Movies Frighten Children and What We Can Do to Protect Them, Cantor offers the following guidelines for what is and is not appropriate viewing material for children. Scenes in movies or TV shows that parents should keep away from this age group include:

• Visual images—whether realistic or fantastic—that are naturally scary, like vicious animals, monsters and grotesque, mutilated, or deformed characters.
  
  
• Physical transformations of characters, especially when a normal character becomes grotesque.
  
  
• Stories that involve the death of a parent.
  
  
• Stories involving natural disasters, shown vividly.

Cantor believes that as a rough guideline, it's best to wait until a child reaches age four before setting foot in a movie theater; but even then, parents have to be vigilant about what the film and the previews may contain.

If you have a young child who has been frightened by something she's seen on TV or in a movie, try these tips from Cantor:

• Remove the child from the scary situation.
  
  
• Don't belittle or ignore the fear.
  
  
• Provide your physical presence, attention, and warmth.
  
  
• Try a drink or a snack and a new activity.
  
  
• Consider lower doses of the scary image if the child wants to conquer the fear.
  
  
• Recognize the limited effectiveness of logical explanations (which tend not to work with very young children who believe what they see regardless of explanations).
  
  
• Be firm in your resolve to practice prevention.