We are currently working on a performance task where students have to gather data, apply a line of best fit, determine a rate and then make a prediction. It's been a task to help students shift their thinking from right/wrong to more/less. In other words, I don't want them to see their understanding as binary--I get it; I don't get it. I want them to see their understanding as something that falls on a continuum.
When doing something like finding a line of best fit, I think it's less important to discuss what the line looks like and more important to discuss why a particular line is best. This leads us to the descriptors we've been using to discuss both sides of the same coin:
Concept and Precision
5: Strong concept; Precise
4: Strong concept; Somewhat precise
3: Problem with concept; Somewhat precise
2: Problem with concept; Lacks precision
1: No attempt
Through a few discussions with different classes, the top three descriptors have evolved into something like this.
5: Precise answer with precise method
4: Estimate backed by reason
Then I walked by a student and noticed the self-assessment she was doing.
How's that for kid friendly?