Editor’s Note (2026): Originally published in 1998, this report was among EdTrust’s earliest efforts to examine inequities in the American education system. As part of our 30th anniversary, we are resurfacing this publication to reflect on how far we’ve come and how much work remains.

For decades, there’s been a dominant yet false narrative in education: that students from low-income backgrounds and students of color start behind — and stay behind — because of factors that are outside of schools’ control. But that explanation doesn’t hold up.

Across the country, there are schools and districts where students from low-income backgrounds are achieving at remarkably high levels. These examples challenge a long-standing assumption: that schools can’t overcome the effects of poverty.

So, what’s really making the difference? Teachers.

The Insight

Research — and real-world results — point to a powerful conclusion:

Teachers matter more than anything else inside a school when it comes to student achievement.

Not just any teachers — but well-prepared, well-supported, and strategically assigned teachers.

This report shows that:

• Students perform better when taught by teachers with strong content knowledge and training
• Access to high-quality teaching is not distributed equitably
• Teacher quality is one of the most important — and most actionable — levers for closing achievement gaps

Challenging the Status Quo

Too often, success in high-poverty schools is attributed to “exceptional” leaders or rare, one-off conditions. But what if those explanations are wrong?

The real issue is this: Many students are not being taught the knowledge and skills they need to succeed.

When expectations are low, curriculum is watered down, and access to strong teaching is uneven, achievement gaps persist — not because students can’t succeed, but because systems aren’t designed for them to.

What the Evidence Shows

New large-scale studies — and decades of classroom experience — tell a different story than earlier research suggested:

• Schools do make a measurable difference
• Teachers are the single most important in-school factor affecting student learning
• Ensuring equitable access to strong teachers could cut the achievement gap in half
• Strategically assigning the most effective teachers to the students who need them most could close the gap entirely

Why This Matters Now

Improving teacher quality and access isn’t a distant or abstract goal — it’s within reach. Unlike many factors tied to student outcomes, this is something policymakers, districts, and school leaders can directly influence:

• How teachers are prepared
• How they are supported
• Where they are assigned

These are decisions — and they can be changed.

What You’ll Learn in This Report

In Good Teaching Matters, you’ll explore:

• The research linking teacher qualifications to student success
• How inequities in teacher assignment impact outcomes
• Why past assumptions about poverty and achievement fall short
• Actionable strategies to ensure all students have access to excellent teaching

The Bottom Line

When students are taught at high levels, they achieve at high levels. Closing the achievement gap isn’t about changing students — it’s about changing systems. And it starts with teaching.

After all, good teaching matters.