I was pretty much a straight A student in high school. I was never offered reward or a punishment for grades. But I did receive constant nagging and a huge guilt trip from my mom if I received less than an A. If I would have gotten an F wow I can't even imagine my mom's reaction... While my mom's nagging WAS annoying I am grateful that she convinced me school was important enough to try my best.

I don't learn things well, I just memorize things well...if that makes sense...I remember it for tests then forget it the next day, I don't feel like I actually learned anything.

I went to college for one year and it was definitely harder than high school, I think I got one C and the rest were A's and B's. I'm trying to convince myself to go back ugh.

Anyway (sorry for rambling a bit) I think that parents should set their kids up for success and encourage them to do their best. If a C is the best they could do and they really tried then they should be proud of them. Unless a child is doing badly because they just don't care and aren't trying then I don't think there should be a punishment.