In my seventh and eighth grade class I have rarely given a student a test to retake. Our high school teachers do some retesting in some classes, but I prefer that they give an average of the two tests. Teachers have given credit for corrections done to a test. Another option we have used is giving the student an opportunity to do extra credit work to lift a grade. I think it is important that the original grade in some way stays as part of their grade.
I have observed that tests often show us what they are intended to show us.
1. They show what the student’s ability is. If the student lacks ability he may benefit from a retest. The student may benefit more from keeping the grade and using other work/tasks/projects within his ability to bring his score up.
2. They show what the student’s effort is. If a student has not put forth the effort to do well they deserve to get the grade they were given. Often with these students their test answers mirror the same quality of answers in the rest of their work.
My observation is that for one reason or another the student received the grade they deserved, so is it honest to give multiple retakes without taking the first grade into account.