Snape and the foe glass; Math classes at Hogwarts

[judyserenity]

No: HPFGUIDX 35638

First, thank you, Porphyria for your excellant reasons why Snape is 
mostly likely not a vampie.   
Now, specifically on the topic of Snape's reflection, Porphyria said:
> the foe glass is *neither here nor there* in terms of vampire 
> evidence. Since some other people were wondering why Snape seems to 
> be so taken with his reflection here, as if he'd never seen it 
> before, I wanted to offer an alternative interpretation for his 
> reaction to it.
[Porphyria then points out that the reflection in the foe glass 
validated Snape's identity as a trusted associate of Dumbledore:}
> The mirror reveals [Snape] to be a 'foe' of "Moody" not 
> because [Snape is] Evil, but precisely because he's Good. 

Porphyria, thank you!  I am so relieved.  I really didn't like the 
other explanation, which is that Snape is a vampire, has never seen 
his own reflection before, and is standing there transfixed at the 
sight of himself, thinking "Egads!!  I really *do* need to wash my 
hair!"


Rollerramla asked:
> If the students enter Hogwarts when they are 11 years old,
> then does that mean that they stop learning math at a 5th grade (or 
> the British equivalent) level?

There has been a lot of speculation here about this.  One theory is 
that the students learn some math during their regular classes 
(trigonometry during astronomy, fractions during potions, etc.)  
Another is that most wizards don't need much math.  There have been 
lots of discussions about whether other subjects are taught at 
Hogwarts.  Music instruction especially seems to be strangely absent. 
Does anyone remember the message numbers or dates of any of these 
threads?

Judy