New research suggests that children who have large oral vocabularies early on enter kindergarten classrooms better at reading and mathematics as well as better behaved.

Researchers at Penn State, the University of California, Irvine, and Columbia University has found that children who are doing better academically in kindergarten are more likely to go to college, get married, own homes and live in higher-income households.

"Our findings provide compelling evidence for oral vocabulary's theorized importance as a multifaceted contributor to children's early development," Paul Morgan, who led the study, said in a statement.

For the study, researchers examined data from parental surveys reporting on the size of their children's vocabularies at two years of age. The researchers found that vocabulary gaps between groups of U.S. children were already evident by this early time period. Females, those from more economically advantaged families, and those receiving higher quality parenting had larger oral vocabularies. Children born with low birth weight or who were being raised by mothers with health problems had smaller vocabularies.

Morgan and his colleagues found that children with larger vocabularies at two years of age were better readers, knew more about mathematics, were more attentive and task persistent, and were less likely to engage in acting out- or anxious-type behaviors. This was the case even after adjusting for the family's economic resources, the children's prior cognitive functioning and behavior, and many other factors.

"Our findings are also consistent with prior work suggesting that parents who are stressed, overburdened, less engaged and who experience less social support may talk, read, or otherwise interact with their children less frequently, resulting in their children acquiring smaller oral vocabularies," Morgan explained.

The findings are detailed in the latest edition of Child Development.