Totally depends on the child.
It might be as simple as 'keep up the good work', especially in year 7 or 8.
Or it might be that they need to approach their work in a different way, or that they are being complacent, or they should have more confidence to speak up, or at least speak to me.
A couple of times I have told parents that their children need to take it a bit more easily and just enjoy the subject . Some children get awfully stressed about things, unnecessarily.
In secondary I tend to concentrate on what the child should do. I don't really assume there will be parental involvement in the actual work.