The first paragraph of the link recommended by Barb Schrank says:
An effective school board plays an important watchdog role in keeping your local school on track, and setting policies that affect your child and your school. The school board sets the vision and goals for the school district, and holds the district accountable for results. One school board member cannot do the job alone. Effective school board members contribute their unique talents while collaborating and working as a team with other board members.
I find the Madison Board of Education and superintendent do well on collaboration, except for attacking Ruth Robarts, but I’d like to see the board improve dramatically on being a watchdog, setting policy, setting the vision and goals for the district, and holding the district accountable for results.