What is the better method?

A prof could add a certain number of points to all point totals (i.e. add 20 points to everyone's grade) or multiply the point totals by a certain percent.


Add points, right?

The fairest way is a bell curve. The way that most like is just adding the points.

Why curve? Offer extra credit and if they do it, they earned it, and if they didnt, you get to teach them again....

Neither, it should be standards based.

With the + you are just shifting the mean, median, and mode to the right. With the % you are changing everything, but those with the higher grades will receive a bigger increase. Say you add 5%, then a kid with a 90 gets a 94.5 (+4.5) and the kid with an 80 gets an 84 (+4). Hence the + is more fair.

Frequently a curve looks for clusters. The highest cluster is defined as the A range, the next highest are Bs, and so forth. Other times, the professor will have decided on a grade distribution... for instance, 15% of the class will get As, 20% Bs, and so forth. He or she may have decided to just make sure the class average is at a certain level. A single point value is added to every student's course score to normalize the grades to the typical 100-point, 10-point interval grade scale in accordance to the instructor's goals. That way the highest performers are rewarded and no grades are killed due to a poorly administered or taught class. A curve corrects the failings of the instructor or course designer, not those of the students.

A multiplication scheme doesn't make mathematical sense.

I don't particularly like the idea of using extra credit as a de facto curve. The grade should be based on the student's understanding of the material, not the amount of time he or she spent on the course.

[This message has been edited by Ulrich (edited 8/21/2011 10:12p).]

I agree with Ulrich. The class usually resolves itself out by distribution, perhaps it would help if you made a histogram of the grades. The grade distribution is somewhat bimodal, and the A's separate themselves out from the B's. Determining the breaks between A/B and B/C can be tricky, but there are usually breaks in the grades too and those help determine the divide.

Profs who have to curve aren't very good instructors. Provide a rubric and a clear list of objectives. If your exams are correctly designed, they should accurately be able to evaluate student mastery of the subject. A curve is basically a professor's way of admitting their statistical error is extremely high.

disagree completely

that's way too broad a statement.

I've had great profs who curved for a variety of reasons (test was too long, test was too hard, etc.)
and I've had absolutely terrible profs who curved because they were terrible teachers and no one learned well in their class

Remember that curves do not have to be positive.

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Why curve? Offer extra credit and if they do it, they earned it, and if they didnt, you get to teach them again....

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This is what I do for my students. Makes it so the curve helps those that are honestly trying and putting effort forward while not hurting those that don't. Never really believed in grade manipulation at all unless I did something wrong that caused bad grades.

Percentage grades or +/- would help A&M a ton more than any kind of curving.

I figure profs get the most headache from kids who are right there at a letter grade and dont get it, or want to get it. A plus/minus system would help that out by allowing higher discritization in scores, thus lower dropoff when you dont get an A or B. Of course it really helps when you get a solid "A", but there are times when that doesnt happen and then a B+ would be really nice to have.

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Profs who have to curve aren't very good instructors

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I also disagree with this statement. It is much easier to separate the good from the mediocre from the bad if the good make 80's the mediocre make 50's and the bad make 30's. Then you have very clear differences between students.

Without a "curve" you'd have to make sure that the mediocre students were only ~10 points worse than the good students. Which would probably come down to a fairly insignificant portion of the test/homework/whatever.

To the question from the OP....neither make sense. As others have said, many profs will simply give ~20% A's, ~30% B's, ~30% C's, ~20% D/F's regardless of what the actual test scores are

I don't see anything wrong with that.

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Offer extra credit and if they do it, they earned it, and if they didnt, you get to teach them again....

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I'm actually against this. It penalizes the A students who studied for their exams in the first place. Unless the extra credit is worth a marginal amount and only swings a select few students (the truly borderline students).

Edit: And, it also creates additional burden on the prof to create/grade the assignment.

[This message has been edited by Ag_Wolverine (edited 10/6/2011 8:38p).]

The term "curve" used by the OP and others is really a poor choice of words. It really implies one is normalizing grades. That means some fixed percentage of students will get an A, B, C, D, and even F. Whenever I have had students ask (usually before the first test) if I am going to "curve" grades I try to explain what they are asking and gladly offer to do that for them. They just have to tell me who in the class would be willing to fall on their swords and take the F for the team. Because someone has to. What the OP really wants to know is what is a better way to inflate grades. And as someone who has been in the business of making exams and evaluating students for more than 20 years, I can count on one hand the number of times I have felt it necessary to adjust grades upwards.

A different issue that I hate is allowing corrections for "some" students. Our high school allows corrections where the student can earn back 1/2 their points if they made below and 80. So say my kid makes an 82 - she gets that and my neighbors kid makes a 70. If the neighbors kid corrects his work he ends up with and 85. There is no way you can convince me that is right.

I didn't use the word "fair", because I didn't want you all to tell me life isn't fair. I know that.

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I'm actually against this. It penalizes the A students who studied for their exams in the first place. Unless the extra credit is worth a marginal amount and only swings a select few students (the truly borderline students).

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One, if the "A" students aren't getting the extra credit while the "D-C" students are, you wrote the question wrong. Two, If anything the extra credit approach will only increase the inequity in grades between the top 50% and the bottom 50%. If extra burden on the prof is ever a consideration, that prof should not be teaching.

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One, if the "A" students aren't getting the extra credit while the "D-C" students are, you wrote the question wrong.

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What does writing a question wrong or right have to do with extra credit? Why would an A student do extra credit in the first place? What is their motivating factor, unless A&M went to a 9.0 grade scale and there is now a A+ stratification?

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Two, If anything the extra credit approach will only increase the inequity in grades between the top 50% and the bottom 50%.

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Maybe I'm not understanding this but please explain to me how extra credit, assignments completed to boost lower performing students to the next grade level, increases inequity? I would think it does the opposite, since you essentially tighten/skew the grade distribution towards the A-crowd.

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If extra burden on the prof is ever a consideration, that prof should not be teaching.

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'Cause professors are hired to help students along with extra course work and not bring in research grants. If you just make a histogram of the grade distribution, and distribute the A's, B's, etc. accordingly, that will be it. There's always going to be A students, and D students.

This thread makes me want to go on a rant about the grading for my heat transfer lab. It's such a joke. Grades on the first few labs were "too high" according to the prof, and now its almost impossible to get an A on a lab report. A rubric is given with categories ranging from 0-5 points. No half points are given, so in each category you either get 60%, 80%, or 100% of the points possible. The TAs basically never give 5's because its always possible to improve. It is total bull***** The nature of a rubric makes it so TAs are hesitant to give 5s because that implies "perfect" and no lab report is perfect. However since no 4.5s can be given, you are instantly dropped to an 80 (basically).

Neither. Ditch the absolute grading system (90-100, 80-89, 70-79) and just give out grades based on the class' overall performance. Look for significant gaps and use those as cutoffs for letter grades.

I generally think plotting the histogram and then looking for clusters of scores is probably the best method.

Son is first year ChemEng.....

With grades being curved how do you know (and when) do you ever know how you are going to come out?

Are the curves already reflected when the tests come back or is the curving done at the end of the semester?

In short, how and when do you know if you are screwed or not?

Squadron7,

Most professors (in my experience) will state what the class average was on a particular test. Any student should easily know if they are above or below average. At the end of the semester, that is what will determine their letter grade. Above average students typically get As and Bs. Below average students probably won't

If the curve is included on the grade for the test, the prof will say so when he gives out the grades.

Many profs will say they don't curve, but they virtually all do in some way. If you are above the class average you'll generally be fine even if your grade was horrible on a 100 point scale. I remember a physics final where out of 10 workout questions, I only got two final answers and I'm pretty sure they were both wrong... got a B.

The fish year math/physics classes are supposed to cull out the weak and uncommitted, and fear is part of the drill. Don't stay out of pride alone because it isn't for everyone, but don't be scared out either.

If you grad on a distribution (bell curve), you can set the grades and go from there. Note: I did this teaching at A&M.

I would look at the average (and median, but usually really close), and go up and down 0.5 SD. That was a B. Above that, an A, below that, C. Even further, 2.5 - 1.5 SD below average, was a D.

You were graded on what you did and how well you did it. Questions were framed from things in class and previous tests. I had a couple of profs do this method and it allows to see where students really are in terms of understanding.


One caveot: if the average was like 85+, then I would not be opposed to giving out A's for everyone (or a few B's). But I never saw that.

~egon

[This message has been edited by Dr. Doctor (edited 12/12/2011 10:40a).]