WordNet (r) 3.0 (2006):

skull session
    n 1: a session (as of executives or advisors) to discuss policy
         or strategy or to solve problems or exchange ideas
    2: teaching strategy to an athletic team [syn: skull session,
       skull practice]

Moby Thesaurus II by Grady Ward, 1.0:

26 Moby Thesaurus words for "skull session":
   assignment, chalk talk, discourse, disquisition, exercise,
   exposition, harangue, homework, homily, instruction, lecture,
   lecture-demonstration, lesson, moral, moral lesson, morality,
   moralization, object lesson, preachment, recital, recitation,
   sermon, set task, talk, task, teaching