Pros – The mission and values (giving all students access to excellent education that will get them to and through college) are shared by all the teachers, creating a strong sense of community and fostering close relationships with coworkers. You are also given almost complete autonomy over your work, which has drawbacks and benefits.
Cons – The compensation, especially considering the work/life balance, is not great. The hours are already longer than a normal school day, and the lack of direction from administrators means you will spend even more time working off the clock to prepare. Some schools focus almost exclusively on raising test scores rather than holistic education.