Students turn in their work papers to me with corrections already marked on it in ink. I ask them to classify their mistake as an algebra error, a physics misunderstanding, or an IDK moment. About 3/4 of the time, kids spot their error as soon as they see the correct answer, saving me the headache of figuring out what was in their head when they were testing. Students get the benefit of leaving the test knowing exactly how well they understood the material (and almost their exact grade on the test).
Here’s how the testing procedure works.
Step 0: Write a Test & Allow 20% Feedback Time
My system works only if the vast majority of your students have the chance to give themselves feedback in the same class period as they took the test. I use the 80-20 rule to plan this time: kids need 20% of the class period to check their work and leave feedback.
Class Period = Futzing Around at the Start of Class + Test + Feedback
Feedback = 0.2*Test
I often will have about1-2 students in a class who don’t have time to do the feedback part. That’s ok. Just plan to allow most kids to do this feedback cycle.
Step 1: Take the Test
though this step would work just as well on a paper test

Students hit submit at the bottom of the test then switch to pen. I monitor the room for cheating because this is the one spot where it could happen.
Step 2: See the Key and Give Yourself Feedback
This requires you to either use a computer-based test as I do or place answer keys around the room for students to move to once complete.
How often does it happen that once presented with the right answer, students will have a “D’oh!” moment where they immediately realize their mistake? This is where you get the best feedback from kids. You can’t mine this kind of academic gold the next day, either. You gotta do the mining immediately after they solved the problems.
If you’re working on paper, you could model your setup on Frank Noschese’s version that inspired me. I’ve provided complete solutions in the past though my current setup doesn’t do that. I think kids are more analytical (critical?) of their own work if they have to find their own path to the correct solution than if they’re comparing their solution to mine line-by-line.
Before you look at my examples, keep in mind my kids are transitioning to thinking of their work papers as “scratch” to a place to demonstrate what they know. So with that in mind, here are a few test papers from this latest round:

I wanted to show you (above) some work that’s ugly to try and read because the student doesn’t organize his work well. If I let him identify the mistake, though, I see exactly where he went wrong. Let’s look at another one that’s tough to spot when grading several class sets but every kid who wants some partial credit will find:

Here’s another one where the kid had a big physics error. The question read “When you blow air across a soda bottle, you produce a tone with a frequency of 253.2 Hz. What is the frequency of the next harmonic?” Students needed to identify this as a closed pipe resonator, which only resonates on odd harmonics, and so the next harmonic is the third. The correct math to do is to multiply the frequency given by three. Most kids didn’t make that realization. When this young lady saw the right answer, se realized her mistake and showed a correct solution.

Step 3: Teacher Awards Partial Credit
Yep, I’m not a SBG‘er. And unless you’re using binary grading, this partial credit thing still makes sense.
Before I start grading, I like to think about the value of different types of mistakes. Usually I’ll grant 3/4 credit for pure algebra errors such as dividing instead of multiplying, 3/4 credit for unit conversion mistakes, and 1/2 credit for getting some of the physics but not all of it correct.
My kids know that the score Moodle awards them is their baseline test grade. On this last test, the average student added 8% to his/her grade through partial credit.
Beneficial Side-Effect
I spend so much less time grading assessments because kids have identified a lot of their mistakes for me. Sure, there will be cases where kids can’t identify their error. My colleague Adrian suggests students can’t do the bulk of this work:
Maybe chemistry (which he teaches) problems are fundamentally different from physics problems. All I can speak from is my experience — kids can often identify where they went wrong on a problem they’re expected to know how to do if I present them with a numeric answer.
I have made myself also go to the questions I got *right* and figure out why those were the right choices (multiple choice test) and why somebody might pick something else.
Thanks for sharing this. I’m having students correct their own quizzes/tests right away as well- though I like your method of having them specify the type of error. So far we’ve only had one quiz and too many students simply marked when they got an answer incorrect. I think requiring them to identify the type of mistake might provide a good structure that can lead to more thoughtful and reflective correcting.
I feel most students do have the ability to check their work effectively- and more likely than not the immediate feedback paired with having to analyze their mistakes helps them to think more clearly about their weaknesses. At the very worst it’s saving you a lot of time, and that’s bad at all. 🙂
Thank you for sharing this WONDERFUL time saving idea. I believe it will benefit the students as much as myself. By looking at their own mistakes, I am hoping they will see the ‘error of their ways’ and learn from it. Less time grading for me means more time to plan, research & gather supplies. It’s a win-win!