There should be parent/community representation at every SPS school's BLT (or should). That representation should NOT be controlled by the principal.
There should be bylaws written and readily available for anyone to be able to access about the decision-making process for each school.
Let us know how the BLT at your school works.
A huge thank you to Ann Donovan who pulled all this info together. Follow her on Twitter: @ann_donovan for great ed news in one place.
School Governance Structures - F20.00
Establishment and Operation of School Governance Structures Procedure - F20.01
Specific Areas of Involvement for School Governance Structures Procedures - F20.02
The SEA Collective Bargaining Agreement also includes additional details regarding the requirements of BLTs, see article II section 4, pages 10-12.
Keep this thread in mind for when school resumes in the fall. I would expect this kind of issue is one the Executive Directors would cover but I'd have to ask. If the district is truthful in its promises for parent engagement and transparency, this would be a good place to start.