The Coal Hill School storeroom was a shack where the caretaker kept his supplies.
In the 2010s, the Twelfth Doctor, in "deep cover" as temporary caretaker John Smith, parked his TARDIS in the caretaker's storeroom. He made a sign that said "Go Away Humans", because he got angry whilst making a "keep out" sign. Courtney Woods entered the building in search of paper towels, and discovered the TARDIS.
The Skovox Blitzer followed the Doctor and Clara Oswald into the storeroom. When the Doctor accidentally started its self-destruct countdown, Danny Pink distracted the Blitzer by somersaulting over it as it fired at him. The Doctor successfully ordered the Blitzer to abort self-destruct, and released it in outer space from his TARDIS. (TV: The Caretaker)