[NathanR]

Are these teachers uncertified because they don't know the subject, or because they don't have teaching certificates? (I expect the latter.)

[Amelia]

Are these teachers uncertified because they don't know the subject, or because they don't have teaching certificates? (I expect the latter.)

The article didn't say. Some substitutes in our system are retired teachers, and some are "warm bodies" - I don't know about this system.