The Mirage

Do we know how to help teachers improve?

The Mirage challenges the widely held perception among education leaders that we know what works when it comes to teacher development, and if we could just apply that knowledge more widely, we could improve the quality of classroom teaching in short order.

Over two years, we looked closely at teacher development in three large school districts and one charter school network. Here’s what we found:

• School systems are making a massive and laudable investment in teacher improvement—far larger than most people realize.
   
• Yet most teachers do not appear to improve substantially from year to year, even though many have not yet mastered critical skills.
   
• We found no evidence that any particular kind or amount of professional development consistently helps teachers improve.
   
• School systems are failing to help teachers understand how to improve—or even that they have room to improve at all.

But school systems shouldn’t give up on teacher development. And they shouldn’t cut spending on it, either. Rather, we believe it’s time for a new conversation about teacher improvement—one that asks fundamentally different questions about what great teaching means and how to achieve it.