A question about wizard children

[sym_2_one]

No: HPFGUIDX 43945

This is another question that's been bothering me, ever since I read 
the first novel.  

What in the world to wizard children do before they attend Hogwarts, 
if they are able to attend at all?  What happens to kids under the 
age of eleven if both parents have to work? How do they learn to 
read, write, and do simple math?  What if a wizard child is not 
offered to attend of School of Magic?

Maybe someone has already answered this, or maybe there are no 
answers, but I'd surely like to know if one exists.   

"sym_2_one"