Two OVAs released with the 8th and 10th volumes of the original novel. They fall chronologically between the first and second seasons. Season 1, Episode 13:
Haruna is given the task to hold a Spring Festival at the local shrine, in her own magical-Equipment-girl way, of course... Seraphim does not want to be a freeloader at Haruna's and Ayumu's place, so she starts cooking... And a concentration-game contest in the school's main assembly hall pushes Ayumu and Orito to their limits... (Source: AniDB) Season 2, Episode 0 part 1:
Haruna wants to play more with Hellscythe at a swimming pool.
Season 2, Episode 0 part 2:
Hellscythe's birthday is near! Haruna prepares a birthday party for Hellscythe in her own magical-Equipment-girl-way. What kind of party could Haruna be holding? What kind of birthday presents will Ayumu and gang give to Hellscythe?
Following the death of District Attorney Harvey Dent, Batman assumes responsibility for Dent's crimes to protect the late attorney's reputation and is subsequently hunted by the Gotham City Police Department.
A veteran chef faces off against his restaurant group's new CEO, who wants to the establishment to lose a star from its rating in order to bring in a younger chef who specializes in molecular gastronomy.