How I Curve A Test

My school just wrapped up our first quarter last week, and that means…. midterms! Every teacher has their own way of grading and the word “curve” can mean so many different things. I want to share my favorite way to curve tests, taught to me by my favorite math teacher, my dad.

Most of my assessments are out of 100 points. First I make all the points add up to about 80. For example, if I have a 10 question test, instead of each question being 10 points each, they would each be 8 points. So if a student misses the question entirely (no partial points), it would be -8 instead of -10. The scores would then look like the following

**Benefits: **

**1. Helps the Bottom Scores the Most **

As you can see, this way of curving helps the students at the bottom the most. A student who missed half the questions no longer has a 50%, they get a 10% jump! Whereas the students at the top still really have to earn their scores. What I like about this is that if a student is failing, their score will still reflect their knowledge (a “D” is still reflecting low content knowledge), but won’t ruin their overall grade if they improve on future assessments.

**2. Scores Still Reflect Content Knowledge**

I also like that it still makes the students who earn A’s and B’s really earn it. I’ve never liked adding a set amount of points to each test, for this reason. If I choose to add 20 points to every test, a 40% might become a 60% (which in my opinion is ok because both of those scores reflect a similar content knowledge), but a 75% becoming a 95% does not seem fair. Those two scores represent very different levels of content knowledge.

**3. It’s Flexible!**

You may not have a number of questions that will be divisible into 100, and that’s ok! In this case, I try and aim for my point total to be between 75-80. So for example, let’s say I have 22 questions on my test. If my assessment is out of 100 points, each question is then worth 100/22, or 4.55 points. Instead I’ll take off a maximum of 3.5 points per problem for a total of 77 points. Depending on your class dynamic, you may chose a different range. If you’re teaching an advanced or honors course, you might choose a range of 85-90. If you’re teaching a remedial course you might choose 70-75. It’s up to you and what you think is best for your students!

One more thing to mention is that I try and give partial credit whenever I can. If the most I take off from a question is 8 points, I still might only take off 2, 4, or 6, depending on what the student wrote and what mistakes were made.

Here are a few more sample scenarios:

If my assessment has 25 questions, I’d take off 3 points each, instead of 4.

If my assessment has 40 questions, I’d take off 2 points each, instead of 2.5.

If you've never tried curving your assessments before, and are dealing with failing grades, give it a try! Let us know how it goes, or let us know of another curving strategy that you like to use!

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