Hogwarts-History in the making

Welcome to the new school year of Hogwarts!
A thousand years or more ago
when I was newly sewn,
there lived four wizards of renown,
whose names are still well known:
bold Gryffindor, from wild moor,
fair Ravenclaw, from glen,
sweet Hufflepuff, from valley broad,
shrewd Slytherin, from fen.
They shared a wish, a hope, a dream,
they hatched a daring plan
to educate young sorcerers
thus Hogwarts School began.
Now each of these four founders
formed their own house, for each
did value different virtues
in the ones they had to teach.
By Gryffindor, the bravest were
Prized far beyond the rest;
For Ravenclaw, the cleverest
would always be the best;
For Hufflepuff, hard workers were
Most worthy of admission;
And power-hungry Slytherin
loved those of great ambition.
While still alive they did divide
Their favorites from the throng,
Yet how to pick the worthy ones
When they were dead and gone?

'Twas Gryffindor who found the way,
He whipped me off his head
The founders put some brains in me
So I could choose instead!
Now slip me snug about your ears,
I've never yet been wrong,
I'll have a look inside your mind
And tell where you belong!