In a recent Fordham Institute study, Seth Gershenson of American University examined Algebra I grades and test scores from North Carolina public school students to determine if tougher grading standards raised student test scores and produced other positive outcomes.  He summarizes his findings for EducationNext:

Students assigned to teachers with the lowest standards do far worse on an end-of-course exam than their peers with tougher teachers, and continue to underperform those students one and two years later. We know that teachers’ grading standards are an important component to their students’ success, and we have started to identify the characteristics of teachers associated with higher standards—including those that can be influenced through training or experience.

So, who are these tough graders?

First, teachers’ own educations appear to influence how rigorously they grade their students’ work. Teachers who attended selective undergraduate institutions and teachers who have completed advanced degrees both tend to have higher grading standards.

Second, my analysis shows that grading standards adjust based on teacher experience and school settings—findings relevant to policymakers and school leaders considering grading-standard interventions or policy changes. In looking at teacher experience, I see that as years on the job increase, grading standards increase as well. On average, teachers’ grading standards grow more rigorous the longer they remain in the profession, particularly during their first 15 years. Grading standards tend to be higher in middle schools, suburban schools, and schools serving more advantaged students.

It is unfortunate that students in low-income schools are held to lower standards than their more advantaged counterparts.