Via AP: 

Young teachers block a major highway as they chant slogans, one holding a metal pipe, as a federal police helicopter flies overhead in Chilpancingo, Mexico, Thursday, April 11, 2013. The teachers, who are protesting an educational reform that will submit them to evaluation and loosen union control over hiring and firing, left peacefully after negotiating with police. (AP Photo/Alejandrino Gonzalez)

Subject to evaluation? Heaven forfend! “Loosen union control over hiring and firing”. Well that tells you why they are in difficulties right there, that’s worse than us. At least our unions don’t have control over hiring and firing (except of course tenure means people are very rarely fired).

Masks and pipes, looks more like drug gangs, rather than teachers.