Showing posts with label bell curve. Show all posts
Showing posts with label bell curve. Show all posts

Monday, February 28, 2011

Do schools use a bell curve grading system

I was reading an article called “Bell Curve Grading”.  Three parts that I found interesting were:
“In education, grading on a bell curve is a method of assigning grades designed to yield a desired distribution of grades among the students in a class……”
“…Because bell curve grading assigns grades to students based on their relative performance in comparison to classmates' performance, the term "bell curve grading" came, by extension, to be more loosely applied to any method of assigning grades that makes use of comparison between students' performances…..”
“…strict bell-curve grading is rare at the primary and secondary school levels (elementary to high school) but is common at the university level.”
Most elementary to high schools, that I have either taught at or heard of, have abolished the use of a bell curve grading system.  Even though they have formally abolished such a system, does one still exist below the surface?
I started pondering this idea when I heard a teacher talking about her marks.  Three years ago this teacher tried something amazing in her class and the students’ achievement increased drastically.  This achievement was demonstrated by the class average being over 90%, where in other years it was around 65%.  This teacher felt uneasy giving such high marks to most of the students in the class.
I asked this teacher, “What is the best class average to have?”, the response was “65%-75%”.  After our conversation, I proceeded to ask other teachers about the “best” class average, and every single one of them responded with a mark in the range of 65%-75%.  This sounds very similar to grading on a curve.
Wouldn’t the best class average be 100%?  Most would say this absurd; one teacher informed me that if I had a class average of 100%, I better have been teaching robots!  I laughed at the teacher’s comment about robots, and was informed we are teaching humans and as humans we make mistakes.  To give 100% to a student is truly saying this student has never made a mistake in the class.
My heart sank.  We should not be grading students on what they have done throughout the course but what they can demonstrate at the end of the course.  I fear that if you ask some educators they will say they “desire a distribution of grades among the students in a class”, which is “bell curve” grading.
Grades should not be based on what the class is learning, but actually what the student came in the class with and what the student has learned throughout the class.  My last question to all educators out there: “How many times have you given 100% to a student in a course?”  Most who I have asked have informed me that they never have.  I truly feel sad when our highest mark for a course is set outside the reach of a student.  In a sense we are asking students to run a race they have no chance in winning, and we are disappointed when they don’t finish first.