Dear principle:

I think that changing policy so that students may not participate in sports or other activities unless they have at least a grade B average is a good idea. Students mostly don't try hard unless they're rewarded. If you change this policy maybe students will try on they're best to get a grade B or above. They will see their friends playing all these activities on their hard and best work. So next time they would want to try hard and play those activities.

On the other hand though, not every kid is good at every subject. If kids try their best on the subject and still don't get a grade B average, this wouldn't be fair to them. They would be a lot of students who wouldn't agree with me because of this reason.

Changing school policy isn't a great idea, but to make the students get good grades and to benefit their lives, in that case then it would be good idea. Not every students will agree with me but that's the best way to get them educated even though it wouldn't be fair.

sincerely yours,

STUDENT_NAME