Saturday, August 31, 2013

Grading Students? Stop using percentages

How to grade (assess) students is an important topic in the educational reform movement.

~ As a student, I studied education courses and, in hindsight, noticed that little time was spent on the topic of how to best GRADE (assess) students' work.
~ As a teacher, (10+ years), I gave out  many grades to students.
~ As Potsdam Central Board of Education member (13 years - with 2 years as president and 2 yrs. as vice-president), I spent a significant amount of time studying about grading. How was it being done at PCS? Why? Was it effective? Fair? Consistent? Problematic? Helpful to students, parents, and teachers? What was the latest research? What were students, teachers, and parents telling me about problems with grading practices?
      What I learned from my examination and study of the issue was that the existing methods used at PCS to grade students needed to change. Here is just some of what I learned:
* Some teachers were grading (instead of evaluating) practice homework - thus making each homework assignment, in effect, a test/quiz (at a time during the learning process when mastery was not yet to be expected).
* Some were not evaluating and returning homework assignments in a timely manner (or at all).
* Some were boosting academic achievement grades due to good behavior or lowering academic grades for bad behavior (an important reason to have separate grades for academic achievement and behavioral factors).
* Instead of learning effective classroom management skills, some (granted a small minority of teachers) were using the threat of lowering grades as a tool to control student behavior. Even one teacher, who in many high schools may have over 100 students per day, can do significant damage to students if his/her use of grading is flawed.

  There is no question that there was a need for the Board to develop a philosophy and policy to oversee this most important (and oft unexamined) part of school life.
       Because the BOE president has the authority to form ad hoc committees to study issues, I decided to do just that. Despite the superintendent's reluctance to delve into this potentially politically-charged issue - correctly predicting a turf war - he did, eventually, do a good job studying the matter and working with me and the Grading Committee to craft a new policy.
      I continue to study the issue of grading and so it was with great interest that I came across another scholarly article about grading. The September 2013 edition of Educational Leadership contains a well-researched article entitled, "The Case Against Percentage Grades." Among the points made by the author Thomas R. Guskey:
  1. Percentage grades are popular but cannot be defended "from a procedural, practical, or ethical perspective."
  2. Teachers vary widely in their grading of identical student work (when using a percentage scale).
  3. When teachers use grading scales that have fewer and larger categories (like A, B, C, D, F), there is greater consistency across teachers in the grades assigned to students.
  4. "Percentage grades continued to be relatively rare in US schools until the 1990's."
  5. "The resurgence of percentage grades appears to come mainly from the increased use of technology." 
  6. "The 100-point scale that teachers employed in the early 20th century was based on an average grade of 50, and grades above 75 and below 25 were rare. IN contrast, most modern applications of percentage grades set the average at 75 and establish 60 or 65 as the minimum threshold for passing. This practice dramatically increases the likelihood of a negatively skewed grade distribution that is 'heavily gamed against the student.'"
  7. In a 100-point percentage rating scale:
          *   Are there really 100 discernable levels?
          *  If 65 (or 60) is the threshold for passing, then this type of scale identifies 60 or more distinct levels of failure an only 40 levels of success. Can teachers really differentiate 60 levels of failing?
           *  Many assume the 100-point grading scale is more accurate than a five-point scale. The research suggests this is an illusion.  There is more room for subjectivity and error on the part of the teachers in the 100-point percentage model.
         8. "Students who are taught well and provided ample opportunities to practice and demonstrate what they have learned typically find well-aligned performance tasks or assessment questions much easier than do students who are  taught poorly and given few practice opportunities. Multiple factors influence students' performance, many lying outside students' control." In other words, poor student scores are sometimes a reflection of poor teaching.
          9.  ZEROS! The expression ZAP (zeros are not permitted) has caused quite a stir among those who are seemingly ill- informed and/or resistant to change. Some states have passed legislation "stipulating that the lowest percentage grades teachers can assign to students is 50 rather than zero."  Opponents claim that schools are giving students something for nothing. However, failing is failing and 50 is a failing grade in most schools that use a percentage system. In addition, "...although some have suggested that minimum-grade policies promote grade inflation and social promotion in schools, well-designed, longitudinal studies show that is not the case." (See Carey & Carifo, 2012)
          10. What is the wisdom in eliminating zeros and making 50 the lowest grade (in the 100-point grading system)?
           a. A zero can have a devastating effect on a student's percentage grade. One grade can unfairly skew the overall average.
           b. "A single zero can doom a student to failure, regardless of what dedicated effort or level of performance might follow."
           c.  A grading system (based on 100 points) that permits zeros gives students virtually no hope of grade recovery. A student who has no hope will exert no effort - a problem for both the student and the teacher.

      What's the solution? According to Guskey, schools should consider going to a 0-4 integer grading scale. This would allow schools to avoid the Zap debate and would align school grading with "the levels used to classify student achievement in most state assessment programs." It would also align public school grading with the grading practices utilized at many universities.

    It makes sense to move from a percentage grading system to an integer grading scale. Schools run by progressive thinkers who put students' needs first are likely to make this grading change. It is a win-win for students and districts but will require leadership from insightful educators and Board members.

To quote Guskey, "It's time to abandon grading scales that distort the accuracy, objectivity, and reliability of students' grades."

1 comment:

  1. This is exactly what I was looking for. Well put together!

    ReplyDelete