Potions class,

dark dungeons, too.

Vials of glass,

hold the brews.

~~~

Severus Snape,

Head of Slytherin,

controls his class

with great precision.

~~~

Pewter cauldrons,

hold boiling water.

Gets melted with

Neville's potions.

~~~

Simmering, gurgling

potions brew.

They flow through

The veins of all students.

~~~~~~~~~~~~~~~~~~~~

That's it! Rather short in my opinion, but I like it nonetheless.