As a kid, I was never rewarded for getting good grades. I never found it too difficult and wasn't self motivated either. All the way until highschool I only saw it as another chore.
My mom always made sure I knew that getting good grades was (technically) the only responsability I had; but my parents never gave me anything for good grades (not even congrats, lol). The three times I remember getting something was when I finished elementary school, when i was done w secondary and when i finished highschool, and on those three occasions we went out to eat at a restaurant, something that was really cool because we almost never did.
Dont wanna show off
but got 10/10 in elementary (6 years), 9.9/10 in secondary (3 years) and 9.7/10 in highschool (3 years), which i imagine, is close to As and near 3.8 gpa?? Idk haha
And no, I never liked going to school but I didnt have many choices either. It's school or work in a factory, lol.
But I did have friends who got cool stuff when they got good grades, and I always wished I had gotten stuff too. Unfortunately, my parents couldn't afford buying us stuff or giving us money.
Now that I am in college, well.. almost done, my reward is knowing I will have better opportunities for a good job in the future (doing something I actually like).
I do think rewards are important, even if they are yearly. Not to thank your kid for good grades, but to show them that you acknowledge their effort.