They are very, very, very slow. Boot time is horrible. They take forever to do simple tasks and the screens are horrible. Non IPS screens. Plus, it's a high school, sometimes keys are missing or the computers don't turn on.
It's safe to say that plastic MacBooks are past their prime in this SSD/Retina time, but back in the day they were alright and at least they're still usable today (especially with an SSD upgrade).