Thinking Caps are used to preserve the integrity of the tests during Midterms and Finals. They are made of a thick white cloth that goes around a prodigy's head and into a point, as well as an amalgam of metals that dulls telepathic abilities. Sophie thinks that they look like smurf hats. The hats don't block Sophie's Telepathic abilities, which amazed Tiergan to the point that he instantly gave her a hundred on her telepathy midterms. Variants of this product have been created, as shown through the hat the ogre rebels used to block Grady's mesmerizing in Book 5.