This page may contain spoilers for Star Trek Into Darkness, which won't be released in North America to general audiences until May 16th. Read at your own risk.
A learning pit was a standard form of education on Vulcan. The student was placed in a sunken pit which projected holographic images with a voice asking questions.
Spock answered math questions while in a learning pit.
The learning pits were the site of the thirty-fifth attempt by a group of bullies to illicit an emotional response from Spock. Upon their success, by calling his father a traitor and his mother a Humanwhore, Spock pushed one of the bullies into a learning pit and physically assaulted him. (Star Trek)