Just a few years of high-quality early childhood education could close the academic achievement gap between low-income and affluent students, a new study suggests.

The study, conducted by two university professors, analyzed previous data from a now-defunct program that offered free preschool to students from different social backgrounds. Using this data, the researchers found that after providing low-income children with quality preschool early in life, the kids had the same IQs as their wealthier peers by age 3. This stands in contrast to the IQ gap that typically exists between affluent and low-income students at that age.

The study also showed that quality early education has long-lasting effects on low-income students. For example, although students analyzed in the study were not offered preschool past the age of 3, by age 5 and 8, they still had IQs that were more similar to their wealthier peers than is typical. At the same time, while the IQs of low-income students in the study appear to have been hugely impacted by preschool attendance, the IQs of more affluent students in the study remained standard for their social class.