Published in School Effectiveness and School Improvement, the research shows pre-schoolers whose parents regularly read and talked about books with them scored better on math tests at age 12.

"Our results underline the great importance of exposing children to books for development not just in literacy but numeracy too: early language skills not only improve a child's reading but also boost mathematical ability," said the study lead author Simone Lehrl from University of Bamberg.

For the findings, researchers studied 229 German children from age three until secondary school and participants' literacy and numeracy skills were tested annually in their three years of preschool (ages 3-5) and again when they were 12 or 13 years old.

They found that children gained from home stimulation in their preschool years in literacy, language and arithmetic skills which, in turn, led to higher outcomes in reading and mathematical skills in secondary school, regardless of the home learning environment then.

"Encouraging caregivers to engage with their children in direct literacy activities, shared book reading and advanced verbal interactions during reading and to include language and mathematical content during these activities, should promote children's reading and mathematical abilities in secondary school. Such experiences lay a strong foundation for later school success," Lehrl said.

According to the researchers, the effect also worked the other way with the quality of parent-child interaction regarding mathematics also improving children's language skills.