Saying you taught it but the student didn't learn it is like saying you sold it but the customer didn't buy it.
Learning is something students do, NOT something done to students.
Grades dilute the pleasure that a student experiences on successfully completing a task.
To control students is to force them to accommodate to a preestablished curriculum.
Assessments should compare the performance of students to a set of expectations, never to the performance of other students.
John Dewey reminded us that the value of what students do 'resides in its connection with a stimulation of greater thoughtfulness, not in the greater strain it imposes.