One Harry Potter Has A Theory About Why The Classes Are So Small! / 92.5 Fresh Radio Edmonton Amanda Propp May 26, 2016 06:58 pm According to J.K. Rowling, there are about 1000 students at Hogwarts but there the amount of boys in Harry’s class was a paltry 18 or something like that. The math seemed fishy and this fan has one heck of an explanation. Prepare to have your mind blown! Whoa!!! More here.