I live with my 9 year old cousin who dislikes and has been doing poorly in math. (New Canadian education system likes to have "no homework" because apparently this will be good and reduce stress in kids, but math like other skills requires practice)
He has written on an assignment answering what he wants to be (a scientist) while also declaring that he hates math.
He seems to think he knows the material (the grades beg to differ, especially at this level when there shouldn't be part marks), and claims he knows the technique but just makes mistakes. (Really at the elementary school level it's about both and the results for basic addition,subtraction, division and multiplication will be foundational moving forwards.)
How can one encourage him to stop whining about it and just grind it out to get better? He's getting additional practice now (as would be necessary to improve his grades) however how can one promote autonomy and try to get him to stop dragging his feet about it all the time?
Edit: 9 year old's parents were already on board with getting the kid more math practice. I was looking for any way to help make the kid less whiny about it to reduce what I perceive to be friction being generated in the household. (eg kid is whining, additionally kid won't independently practice meaning a parent gets stuck babysitting and whatnot)