According to the study, published in the journal AERA Open, beginning in early elementary school boys outperform girls in math – especially among the highest math achievers.
This leads to teachers giving lower ratings to girls' math skills while both the genders have similar achievement and behaviour towards the subject.
"Despite changes in the educational landscape, our findings suggest that the gender gaps observed among children who entered kindergarten in 2010 are strikingly similar to what we saw in children who entered kindergarten in 1998," said Joseph Robinson Cimpian, Associate Professor at the New York University.
Data showed that boys and girls began kindergarten with similar math proficiency, but disparities developed by Grade 3 with girls lagging behind. The gap was particularly large among the highest math achievers.
Research also revealed disparities in teacher perceptions of students, with teachers rating the math skill of girls lower than those of similarly behaving and performing boys.
Finally, the researchers examined gendered patterns of learning behaviours to try and explain why boys are more likely to score as high math achievers.
They found that girls' more studious approaches to learning pay off by boosting them at the bottom of the achievement distribution, but do not help the persistent gap at the top as much.
The researchers explored the early development of gender gaps in math, including when disparities first appear, where in the distribution such gaps develop, and whether the gaps have changed over the years.
In addition to math achievement, they examined two potential contributors to gender gaps: students' learning behaviours and teacher expectations.
Overall, the researchers found remarkable consistency across both cohorts. They observed that the gender gap at the top of the distribution (among the highest achievers in math) develops before students enter kindergarten, worsens through elementary school, and has not improved over the last decade.