Vocabulary. If a child doesn't have a word in his oral vocabulary, then learning it is like learning a foreign language - he must learn both the word's meaning and how it looks. A child's vocabulary can be tripled with work, but Wagner says the improvement doesn't have an enduring effect.

"What we can have a bigger effect on is which words a child is carrying around in his head," he explains. Researchers have identified the words children are most likely to see in early reading texts (Seuss wrote The Cat in the Hat in response to a challenge from his publisher, who supplied a list of words first graders were likely to know or be able to decipher phonetically).

"If we can make it so you're carrying around the 100 words you're likely to come across in early reading, that's going to help you," Wagner says. "And that's a reasonable goal."

Distinguishing between print and pictures. Children who understand the difference and know how print works - from left to right - are on their way to reading. Wagner isn't sure whether this is a precursor to reading or a byproduct. But children whose parents read to them often shouldn't have a problem acquiring this skill. To check, you can ask your child to point to the pictures or to the words. It also helps to run your finger along the type as you read to your child so he or she understands the left-to-right idea.

Parents, Wagner says, ought to encourage reading and language development, taking every opportunity to talk with their children (see Word Play, page 51). He recalls sitting by a pool and watching a mother walk by with her two-year-old, talking with the child as though he were an adult. At first, Wagner thought it was silly because the child could not possibly understand everything.