If you were a teacher, How would judge the achievement of students in your subject?

I would use all kinds of assessment to get information about the progress of students at all levels of learning. This includes paper and pencil tests and performance based assessment.

I agreed with Mr. Popov and for addition, I use authentic assessment for judging students' achievement.

I agree with all answers

I wouldn't judge, since all students have a different way of learning. Tests and exams are a method to track progress. But in the event that a student is passing, I will reward them with relieving them of assignments or making the assignment easier. For those who are not doing so well I would have them repeat the assignment and offer some tutoring help. It is important for teachers to extend their hands out for those who are not grasping the lesson, ask the student what they don't understand and offer a solution or another way of teaching so the student gets it.  Teachers should not give up on the student.

it depends upon his/ her understandability.

I am not were, I AM a teacher and I judge by exams, tests, every lesson tasks and counteraction