First, give an exit slip to your students based on a particularly important concept (PIC) for which you want to check for understanding.

Next, sort the exit slips into piles based on the method students chose to use (whether they used it perfectly or not). Choose two examples from the student work that highlight one or two probably misconceptions students still have on the chosen PIC.

Remove identifying information from the student work, photograph it (or use a document camera) and show it the next day in your class. Ask students a question about the work that requires them to think about the work. “Which one of these two examples is correct?” is not a very good question because it can be answered by guessing. “Why do I really want these two students to talk to each other about their solution?” is a good question because if students answer it, they will have to think about the concept a bit differently.

Repeat this every day.

Great idea. I love the discussion opportunities this would generate. Perhaps you do this but it was unstated was following the discussion allow time for the students to make corrections to their work or try the other method. The other students receive enrichment. While that turns it into a 10-15 minute formative assessment, it’s time well spent.

I’ve used quick sorts as well, however I sort them into 3 piles: exceeds, meets, and not yet for the purpose of identifying who understands the mastery objective. Then provide feedback in the form of questions. For example if 6th graders are finding the area of a triangle and they are multiplying the two known sides I might write, “How can the base and height help you?” Then they are returned to students to continue work.

Many of my students are able to identify other students’ handwriting so I would probably project work from another class. Or digitize them to save for the future classes.

Like you said, “Repeat this every day.” I need to do this.

Yeah, it would probably take longer in class if you ask students to revise their work. My thinking was that the preparation for this activity takes 5 minutes of teacher time outside of the classroom, and potentially 5-10 minutes of class time.

Actually, I can think of lots of reasons, but in the spirit of closing the formative assessment feedback loop as moment-to-moment as possible, you might like this Teaching Channel video on “My Favorite No”: https://www.teachingchannel.org/videos/class-warm-up-routine

(I think the particular example filmed is not the most wonderful, but the core strategy is a great idea – giving a concrete thing to work with but pushing for some potentially complex reasoning.)