The Students on board Stellvia are informed of a Competition between foundations, and are motivated to do their best by Kent Austin of the Big 4, he tells them whoever wins the Competition will be considered for the Great Mission, everyone is now motivated to do their best
The instructors inform the Big 4 of the importance of Winning the Astro Ball event, and are told to bring the glory back home to Stellvia, the Big 4 then tests the students in a difficult task in search of a fifth member of the team, and Shima is the only one that manages to come out on top and get past the Big 4, and so she was invited and accepts to be in the Big 4"s (Stellvias) Astro Ball team at the event.
もうすぐ５つのファウンデーションがたがいの技量をきそい合う合同体育祭がはじまる。そのため、授業はとてもきびしい特別訓練がおこなわれ、予科生たちは悲鳴を上げる。
合同体育祭へのやる気をあまり見せない予科生たちにたいし、ビッグ４のひとり・ケントは、各競技の優勝者はグレート・ミッションへの参加もありえるということと、花形競技「アストロボウル」に予科生からひとり出場させるということをつげる。がぜん、やる気が出てきた予科生たち。そんな中、アリサや大たちは、成績優秀の志麻がなぜ操縦技術だけヘタなのかをしらべることにするが…。
