Washington ? Should preschool be more about ABCs or learning to play with others? With the help of Twiggle the Turtle, scientists found out that youngsters do better if they do both.

So concludes a major study in Head Start programs in Pennsylvania, research with implications for preschools and parents everywhere.

Face it, 4-year-olds are lovable but self-centered, impulsive and prone to meltdowns. Teaching them not to whack a classmate who snatches a toy is a big part of preschool socialization.

But growing awareness that early learning is important to future school achievement has put more pressure on preschool’s academic side, especially efforts to eliminate achievement gaps between low-income and wealthier students.

Both skills are intertwined, said Penn State University psychology professor Karen Bierman, who led the new study.

To prove the relationship, Penn State researchers turned to Head Start, the federal preschool program for poor children.

With funding from the National Institutes of Health and other federal agencies, they divided 44 Head Start classrooms with about 350 4-year-olds. Half taught a traditional Head Start curriculum.

The other half added to their traditional teaching a program called REDI Head Start that included weekly special social lessons – animal toys, such as Twiggle the Turtle, or stories that teach specific problem-solving skills.

By year’s end, preschoolers given enriched instruction scored higher on tests of school readiness, both social and academic, Bierman reported Friday in the journal Child Development.

Some examples: 70 percent of kids in the enriched classes showed little or no disruptive behavior, compared with 56 percent in the regular classes. Twelve percent of the enriched students still struggled to focus attention on academic tasks, compared with 21 percent in regular classes. And 20 percent in enriched classes exceeded a national vocabulary norm compared with 15 percent in regular classes.