バカテス」 by (chocho)

According to BakaTest News vol.11, a 「Baka to Test to Shoukanjuu」 OVA will be released prior to the TV premiere of the second season — which is slated for 2011. No details or release date are available for the OVA at this present time.

[UPDATE 08.27.10] – Promotional video now available:

[Source]