Don’t manage teachers with data

Don’t manage teachers with data. Manage your teachers with your theory. Manage your theory with the data.

There are games of skill like chess. There are games of chance like slot machines. Most of life is a mix of skill and chance, like poker.

If there is an element of chance involved, it is dangerous to judge individual efforts purely by individual outcomes. The outcome can depend on lots of things and you can badly misjudge the worth of the individual effort. In her book Thinking in Bets, inspired by poker, Annie Duke calls this “resulting”. Individual results are not always definitive where some level of chance is involved. It’s not that there isn’t a connection between action and outcome, but it is obscured by noise.

In these circumstances, all you can do is add up lots of efforts and lots of outcomes over time and ask whether the big picture confirms or contests your underlying theory of what works. You manage your theory using this data.

If the data undermines your theory then think again and try something new. If it backs your theory, then keep doing what your theory says is right. You’ll have good days and bad days, but you will have more good days than bad ones.

This is important in many spheres of action, but it is particularly important when it comes to performance management in schools. It’s not that I don’t think data is important here. And it’s not that I don’t think we should manage performance. It’s the connection between the two that I worry about. There are many variables outside a teacher’s direct actions driving the outcomes of a single lesson or even a whole year.

Is chance such a big deal in teaching? When careers depend on the performance of a handful of students with turbulent home lives in a test lasting a couple of hours… yes, chance is a big deal.

Although ‘results driven management’ feels rational and tough, in these circumstances it could be inappropriate. Better to work together to generate a shared picture of what generally works – constantly tested against overall results – and work to implement those practices consistently. Ironically, we should really be providing ‘input driven management’.

Help individual teachers to do more of what the overall data suggests are the right things. There will be good days and bad days, good years and bad years. But there will be more good days and years than bad ones. And a less toxic environment – holding people accountable for results outside their control is not a good idea. A school is not a chessboard.


For another angle on thinking hard about inputs before outcomes (without denigrating outcomes), this blog on curriculum leadership by Claire Stoneman is really good.

One thought on “Don’t manage teachers with data

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s