What researchers studied

Administrative longitudinal study that develops and validates teacher-level measures of average grade inflation and passing-grade inflation using high-school records from Los Angeles and Maryland; Maryland records are linked to postsecondary and earnings outcomes.. Administrative high-school data from Los Angeles Unified School District and Maryland public schools, with Maryland students linked to later college-enrollment and earnings records.

What they found

  • Teachers who broadly awarded higher grades than students' observable performance predicted had moderately lower cognitive value-added and slightly higher noncognitive value-added, but grading leniency was empirically distinct from teacher value-added.
  • Exposure to higher average grade inflation reduced students' later test scores, high-school graduation, college enrollment, and earnings.
  • Passing-grade inflation—a teacher's tendency to move students across the fail/pass threshold—reduced the likelihood of being held back and increased high-school graduation, with more limited long-run effects.
  • The contrast suggests that 'lenient grading' is not one single treatment: broadly lifting grades and helping a marginal student clear a pass threshold can have different consequences.

What the study does not prove

  • This is a March 2026 NBER working paper and should not be described as a peer-reviewed journal article unless a later publication is independently verified.
  • Students were not randomly assigned to a grading policy; the study relies on validated teacher-level measures and administrative variation, so causal interpretation depends on the research design assumptions.
  • Average grade inflation is inferred relative to students' observable performance and characteristics and therefore cannot capture every unobserved classroom or teacher difference.
  • The findings come from Los Angeles and Maryland high schools and should not be generalized automatically to every district, course, age group, or grading system.
  • The paper's large lifetime-earnings calculation depends on longer-run projection assumptions and should not be repurposed as a parent-facing guarantee or dollar estimate for an individual student.

Evidence strength: Strong large-scale longitudinal administrative evidence; validated teacher-level grading measures; NBER working paper; not a randomized trial.

Why this matters for families

An easier A and a rescued passing grade are not the same thing. A 2026 NBER study found worse long-run outcomes when teachers broadly inflated grades, but different effects when leniency specifically helped students cross the pass/fail line. The practical message is to look beyond the letter grade and ask what the student can actually do.

Noor interpretation

How Noor translates the evidence into practice

The Noor Lyra lesson is not that grades do not matter. It is that a grade and mastery are different constructs. Families need both the school signal and evidence that the student can explain, retrieve, transfer, and independently use the underlying knowledge.

When a student's grade improves, verify that the improvement is accompanied by stronger independent performance. Use diagnostics, error analysis, cumulative retrieval, and novel problems to detect whether a higher course grade reflects genuine learning or whether hidden gaps remain. At the same time, recognize that a narrowly targeted intervention that keeps an at-risk student progressing through school can have value even if it does not solve every underlying skill gap immediately.

Read the original source

Noor links to the original or authoritative source so families can distinguish the evidence itself from our interpretation.

Open original source →

DOI: 10.3386/w34952

Research notes

grade inflationassessmenthigh schoolcollege enrollmentstudent outcomesmasterygrading

No single study determines a student's plan. Noor uses research as one input alongside the learner's goals, observed performance, academic context, and response to instruction.