It would be the work of a very few minutes to do a good job of that in Photoshop. Must have been a real hack. The very concept of blacking out what the kid's tee shirt said, seeing that it was nothing obscene or nasty (like "Suck my ___", which would be a common tee shirt design in NYC), is abhorrent. I am very happy to see that teacher suspended, to let them know the severity of what they did---impose their libtard political views on someone else under their control.
The school also stands the cost of reprinting the school yearbooks.