Oh, These Boys

 They love a good potion these days.  Today it is a shrinking potion.  And it must be made in private under the school table.

Ingredients include flour, cinnamon, small toilet paper pieces, and a little water.  And you must stir with a straw.

And looks like someone snuck in a little bit of glue.

Oh no, you don't!  Hands off the table.