Digelidis Ν., Kotsaki Ζ. and Papaioannou Α. 2005. Differences between Junior and Senior High School Students Concerning Intrinsic – Extrinsic Motivation in the Contextual Level, Goal Orientations, Motivational Climate and Perceived Athletic Ability in Greek Athletic Classes . Inquiries in Physical Education and Sport. 3, 1 (May 2005), 77–89. DOI:https://doi.org/10.26253/heal.uth.ojs.ispe.2005.1072.