Hi Cornelius:
Yes, we might find the median or average group performance and that can assist the teacher prepare for their class better.
Pretests can be very short or more comprehensive. They can be done before a major exam to see where work is still needed. They can help clarify what's about to be taught to measure the degree of learning afterwards.
So, there is really quite a lot of benefit and reasons for considering doing these tests.
Regards Barry
