As the American education system continues to stress the importance of student performance, some institutions are finding that pupils may be at a disadvantage due to the curricula.

According to a study published in the American Journal of Education, inconsistent math curricula revise across the country, particularly those who attend schools that do not have demanding lesson plans.

The researchers examined the 1999 Trends in International Mathematics and Science Study, which covered 13 local school districts, nine states and institutions in more than 40 other countries.

According to the findings, those who attended schools with a less demanding math curriculum could not keep up with the performance of students in other nations who had greater standards in the subject.

"Overall, U.S. students are exposed to a less difficult school mathematics curriculum that places them at a disadvantage when compared to the students in many other countries of the world," the researchers wrote.

However, as the nation pushes for education reform, more states are adopting a set of standards that will dictate the exact level of difficulty a math class should be.