"Gap" is a word we hear over and over in the endless debates over our education system. But most people citing or lamenting this "gap" do not define it. Is it proficiency at a basic level in math and reading? If that were the case, the nation could focus on getting every child to that level while admiring schools that exceed the standard.

Finland's education system is much admired, so what if Americans emulated the Finnish concept of the gap? That would be the difference in the performance of students compared with their potential. That is not what we do. Or, what if the standard were the number of students who can read or speak two or more languages? That would massively disrupt the discussion about the gap.

Sadly, the American narrative focuses narrowly on the difference in median scores on standardized tests between racial categories, predominantly in reading and math. Education is stuck in this one-dimensional notion of how to measure achievement. In no other area of life do we do this. We buy houses based on multiple attributes. When we shop for a car, we think about fuel economy, style, safety, even color. Why should we restrain schools to consider only reading and math, and only on standardized tests?

Further, today's students are more different from each other, and more different from previous generations, than any time in American history. It is time we stopped treating them as a bunch of objects to be batch-processed in classrooms. Educators go to conferences all the time where personalization of learning is the topic, sometimes even worshipped. Then they return to their schools where the assumption persists that all students are enough alike that we can expect them to learn the same things in the same way on the same day in the same place and at the same pace. That formula for closing the achievement gap -- however we might define it -- has never worked, and it never will.

If we want to succeed in raising achievement levels, here's how:

Focus first on motivation. If today's students are interested in learning, nothing anyone can do will stop them. If they don't want to learn, there's nothing we can do to make them learn. The key is tapping the intrinsic motivation to learn. That can only happen if the learning environment is designed to do that.

Personalize learning. Confronting every teacher every fall is a wide variation in student proficiency in any subject. If teachers try to meet that with "whole-group instruction," the results will be predictably dismal; the same variations in proficiency will remain at the end of the school year. Only by individualizing the learning experience can the most apt students soar without constraint and the slower students get the time they need without stigma.

Trust the teachers. They are easy targets. The unions fight back, but powerful interests push measures to punish teachers for poor results. The traditional "deal" with teachers was: We won't give you much authority over what matters in school, but we also won't hold you accountable for the results. Today, the proffered deal seems to be: We still won't give you any more authority, but we've decided to hold you publicly accountable for results. Teachers and their unions resist this push, and they should. What if a new deal were offered: We'll give you all the authority you will accept in return for the accountability the public is looking for.

One can only hope that will not be long before some governor or mayor or school superintendent figures out how powerfully these ideas intersect both good policy and good politics. Only then can we hope to begin to narrow the education "gap" -- no matter how it is defined.