Nearly every single aspect of a teacher's job falls under the rules of a union contract. The following is a synopsis of just one of those agreements in Michigan. It comes from Walled Lake Consolidated Schools.
The main source of teacher compensation is the single salary schedule, which pays teachers based only on their years of experience and college degree. Walled Lake's pay scale has 25 automatic 2-to-3 percent annual pay increases. The average teacher salary is $74,105.
Walled Lake teachers also receive generous benefit packages. Teachers pay nothing toward their own health insurance, which costs the district $14,500 annually for a family plan (similar average costs in Michigan are $11,300). A teacher retiring after 30 years with the average teacher salary would net a $33,347 annual lifetime pension (plus health benefits).
The union contract also includes bonus pay, which ranges from $1,500 to $7,000 per year for additional academic certifications or duties. Teachers can also earn anywhere between $700 and $7,000 annually for coaching or participating in other extracurricular activities. The president of the teachers union also gets extra perks, like being released from teaching duties without losing salary or benefits.
Finally, the contract covers working conditions. Teachers are required to be at school for a total of 1,342 hours per year, and can store up an unlimited number of the 11 leave days they get every year. The district then pays teachers for accumulated leave days when they leave the district.
A fully detailed analysis can be found here.