Hogwarts Homework -- Practicing Spells Away From School

[gelite67]

No: HPFGUIDX 114219

If the students are not allowed to do magic away from Hogwarts, why 
don't they get into trouble for practicing spells during the summer?  
It seems like they are required to do that, but I haven't seen/heard 
any mention of an exception to the rules for doing homework (although 
it would make sense).  But, if that is the case, couldn't Harry have 
been practicing a hovering charm in COS or the Patronus Charm in OOP? 
How does the MOM distinguish b/w homework/practice and violations?  I 
assume someone will say the MOM knows what spells are taught at each 
level of school, but does that mean a student can't practice more 
advanced magic, if he's able?

Angie