Baka to Test to Shoukanjuu: Matsuri - Sentaku ni Yotte Tenkai ga Kawaru "LIPS Eizou"
Japanese title: バカとテストと召喚獣 ～祭～ 選択によって展開が変わる「LIPS映像」
Type: ONA
Episodes: 1
Source: Light novel
Genres: Comedy
Studios: SILVER LINK.
Duration: 3 min
Rating: PG-13 - Teens 13 or older

A promotional video that was shown to the public at Comiket 78, and uploaded to YouTube and posted on the official website. It was also included with the first Blu-ray/DVD volume of the Matsuri OVA.

It is done in the style of a visual novel game played on a Nintendo DS screen.

(Source: AniDB)