HOW many classmates?/ Are there an equal number of students in each house?

[justcarol67]

No: HPFGUIDX 91526

Jim ferer wrote:
-<snip> 
> The notion I wanted to argue against is the "5 boys, 5 girls in each 
> house/ each year" argument.  There is strong evidence against it and 
> only assuming for it.
> 
> We're pretty sure there's five boys in Gryffindor in Harry's year.  
> If there's more in another room, we haven't heard about them, and we 
> should have.  We've only heard of three girls: Hermione, Lavender, 
> and Parvati.  We don't know if there's all there is or if there's 
> more, and ****we know nothing about other Houses or other years.**** 
> I say we absolutely can't make any assumptions about any other House 
> or year.

Carol:
Although I agree that five students of each sex per year is a very
small number, that's what the evidence in the early books points to.
There are ten students in Lupin's boggart lesson (eight get to
ridicule their boggart, Harry and Hermione don't, PoA chap. 7) and
there are twenty students in the joint Gryffindor/Slytherin flying
lesson (SS/PS 140) and twenty pairs of ear muffs in the joint
Gryffindor/Hufflepuff herbology lesson in CoS (91). I realize that
these examples don't jibe with the thirty DADA students in OoP, but
they're nevertheless not assumptions; they're canon. We at least have
this much evidence for the two unnamed Gryffindor girls who presumably
share a room with Hermione, Parvati and Lavender, but except for the
OoP DADA class, there's no evidence whatever of any other Gryffindor
boys or girls in Harry's year.

As the examples I cited indicate, JKR clearly started out with 280
students, or at any rate, with 40 students for Harry's year, assuming
that Ravenclaw has the same number as the other three. It's possible
that she decided to increase the number in later books to make it
consistent with her remark about the 1000 students in an interview,
but it's also possible that the DADA class in OoP contains students
from more than one house. I personally think it's just a Flint like
the red and gold Prefect badge that's identical to Percy's silver one. 

Carol