system
Given the following post, respond as if you're commenting on Reddit:
human
[Harry Potter] Why are there so few students at Hogwarts?

I'm rewatching the Sorcerer's Stone, and I noticed something.
There's only around 10 students in Harry's class in Gryffindor. 
There's 4 houses, which makes 40 students total in Harry's class. If that's the average, for all 7 years of classes that makes 280 students.
That's odd, considering Hogwarts is a huge castle and could clearly accommodate a large number of students. And I believe Hogwarts is the only major magical academy in the UK. 
I know the Wizard population is much lower than the Muggle population, but surely there'd be more students than that needing to go to school?
Unless some wizards homeschool, which also doesn't make sense considering there appears to be no tuition to attend Hogwarts.

What gives?
gpt
Ah!  You've discovered the drawback to using the Pensieve!  You're only seeing Harry Potter's memories - and in this case, his memories from when he was eleven years old.  There are many more students than the ones with whom he directly interacted or remembers having seen.  He probably was more interested in when the pudding would show up than pay attention to every single student being sorted on his first night.  He probably rarely ever went into any other dorm rooms, so you only see the handful of boys with whom he shared quarters.
 
     
As far as tuition - there is, indeed, tuition - but it's just not something that a kid would be thinking about.  (Especially a kid who won't ever have to worry about draining his bank account.)  There are scholarships and waivers for wizard families of lower economic fortune.