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In your research and your posts, you frequently state that giving grades less than a 50% is not mathematically accurate. Your logic is that grading should be based on a 10 point scale for each grade. If I perform all of your other 15 fixes, giving students an ample amount of time and opportunity to complete a task, and a student scores 23/50 on a US capitals testfor their highest score (i.e. 46%), isn't that distorting what a student knows and is able to do by changing the grade to 50%?

Matt Slocomb


Yes, if you think about as points but no if you think about it as a level of performance.
23/50 isn't really a problem but 5/50 is because if it is included in the calculation a
student then has to get impossibly high scores to pass. For example, 5 tests out of 50,
pas/fail cut 60%;
Student 1 - 5 20 30 35 40 Average 43% but they passed 3 times out of 5
Student 2 - 5 36 36 36 36 Average 60%


Matt Slocomb's


I guess my point here is that thinking about it as points is more accurate, at least in this
instance. Let's take a more specific example. If I gave a US States and Capitals test, I have
exactly 100 questions. If I students gets 30 states correct and 17 captials correct (47
total), I think using points or percentages more accurately communicates student
performance than if I divided it into a 5 point scale (they would get a 2 on this in most
models I have seen)... The 5 point scale, as suggested by others in the grading reform
movement...0,1,2,3,4. I have seen arguments that 0-20 should be 0, 21-40 - 1, 41-60 -
2, 61-80 - 3, 81-100 - 4. Dividing this way and setting 1 as passing (some have
suggested this) sets the standard really low (on this assessment at least) and distorts
performance (e.g. someone scoring 81 and 100 would both be given a 4). The other point
I think to consider here is that in this instance, the students know exactly what is going to
be assessed ahead of time. Thoughts?

The Grade Doctor's


Matt, I have no objection to the use of points based assessments for right/wrong content but what you then need to do is decide what level of performance is represented by the score the student receives. If the content or the assessment is difficult then the cut scores will be lower than if the content or the assessment is less difficult. Assessment is not as precise as you make it out to be so we should always think in terms of a range for each level of proficiency.