Pros
Benefits are really wonderful. Huge company paid retirement plan - 13% of your salary paid by company with no cap. College tuition for all of your kids!!! A great place if you can find your niche and keep your head down. Just be careful not to do anything to threaten any of the "tenured" leadership. Play the political game and you can have a safe and comfortable living working for a company that is very stable.
Cons
Leadership gets a failing grade. Cronyism rampant. CEO says all the right things but over promises and under delivers. Culture can be toxic. Technology leadership now terrible but keep in mind that this is a very risk averse organization that has a lot of profit at stake every year. People are very territorial as it often feels like protecting their jobs are more important than getting things done. Also this is about the SAT and AP and the colleges, not about what is best for the students - behind closed doors that is not what drives decisions.