How to Help Preschoolers Learn to Tell the Truth Preschoolers (aged 3-5) are learning to grasp the line between reality and fantasy. Telling a fib or tall tale is not an unusual way to explore this boundary at this age. Parents are often hardwired to react hotly to what they see as a lie. But this may not always be the best way to handle the situation.

Pediatrician Tanya Remer Altmann, author of Mommy Calls: Dr. Tanya Answers Parents' Top 101 Questions About Babies and Toddlers, says that when a child's 3, parents often will say, "'Gosh, my child is lying. I don't know what to do.' But it's a fuzzy line between what's real and what's in a child's imagination."

Let's say that your 3-year-old spilled milk on the floor. You ask, "Who spilled it?" and your child says, "Not me." It's not that your child is lying, Altmann says. She may wish she didn't spill it, or if the spill took place an hour ago, she might not even remember spilling it.

Pediatric psychologist Mark Bowers says anyone under age 5 is too young to understand what a lie is. They don't have the same cognitive capacity as a kindergarten-age kid who begins to learn the difference between right and wrong.

"You don't have a future criminal on your hands because your child's not 'fessing up to spilling the milk in the kitchen," Bowers says.