Is a school district considered to be a local government agency or department or would a school district fall under Phase II exemptions?

I grant them Phase 1 as an "entity exercising governmental authority within the United States."

Local municipality Phase I. Same if you have any community colleges.

Would you consider the Local Chamber of Commerce or a Volunteer Fire Department as a phase 1 eligble exemption?

Chamber of Commerce? No. It serves business, but isn't exercising governmental powers.

Volunteer Fire Department? Generally, yes.

Thank you John! What about Athletic Boosters?

What is the government function attributable to such a group?

YOu have to be careful. Sometimes these "booster" clubs act like they're part of the school administration, and even try to use the school's or school district's EIN. Ask yourself who the money belongs to. If it belongs to the school district and the school district supports and controls the booster group (I've never seen such a scenario), you can consider them part of the school district. Even when a school district slaps all kinds of restrictions on such groups, like where and when they can meet, required reporting to the district on activities, restrictions on activities on or off school premises, etc., the clubs are usually separate organizations and not truly part of the district.