No building loses partial power unless it’s a problem within the walls of the school. When power fails at a substation, all power provided by that substation is affected. Only if a building has a generator could it have “partial” power.
>>No building loses partial power unless it’s a problem within the walls of the school.
That is not true. Most schools and commercial/institutional buildings have 3-phase power. It is possible for the utility feed to drop one phase. This will typically cause properly protected 3-phase motors to drop out (kills A/C, fans, etc.), and 1/3 of the lights and power receptacles. That leaves you with 2/3rd of the lights and receptacles, so a lot of things are still operational.